feat(workspace): borderless code blocks, round code/audio/dictation blocks

Code blocks lose border and header bar: language at the top left, a round
copy button at the bottom right on hover; converting back to text moves to
the bullet's action bubble (also for numbered items). Code, audio and
dictation blocks use fixed round corners whatever radius the theme sets.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

CHANGELOG.md

@@ -16,6 +16,8 @@ Das Format folgt [Keep a Changelog](https://keepachangelog.com/de/1.1.0/), die V
 - PWA Web Share Target: Text, Links und Bilder können über den nativen Teilen-Dialog des Smartphones direkt in den MindSift-Posteingang geteilt werden (`share_target` im Manifest, Abfangen im Service Worker via IndexedDB und Übernahme beim App-Start; Fallback-Route `POST /share-target` im Server).
 
 ### Changed
+- Code-Blöcke ohne Rahmen und Kopfleiste: oben links nur die Sprache, Kopieren als runder Symbol-Knopf unten rechts (erscheint beim Überfahren, am Handy immer). „In normalen Text umwandeln“ steht für Code-Blöcke (und nummerierte Punkte) in der Aktionsblase des Punkts.
+- Code-, Audio- und Diktat-Blöcke haben unabhängig vom Theme runde Ecken; Callouts bleiben eckig.
 - Inline-Code ist einfarbig (Text in Haupttextfarbe auf dem Code-Hintergrund des Themes) statt in Akzentfarbe, für bessere Lesbarkeit.
 - Notizen: Enter in einem leeren eingerückten Punkt rückt ihn nur noch aus, wenn danach kein Punkt mehr auf derselben Ebene folgt; sonst entsteht wie gewohnt ein neuer Punkt darunter (auch nummerierte Listen werden dann nicht beendet).
 - Workspace-Leiste: Live, Geteilt und Speicherstatus ohne Rahmen im gleichen Stil, ein senkrechter Trennstrich vor den Notiz-Knöpfen. Footer ohne Linie darüber.

frontend/src/features/workspace/AudioBlock.tsx

@@ -87,7 +87,7 @@ export const AudioBlock: React.FC<AudioBlockProps> = ({ content, canEdit, onCapt
   return (
     <div className="my-1 space-y-1">
       {failed ? (
-        <div className="flex items-center gap-2 h-12 px-3 rounded-card border border-border bg-panel text-xs text-muted">
+        <div className="flex items-center gap-2 h-12 px-4 rounded-full border border-border bg-panel text-xs text-muted">
           <FileAudio className="w-4 h-4" /> Aufnahme nicht verfügbar (offline oder gelöscht)
         </div>
       ) : src ? (
@@ -99,7 +99,7 @@ export const AudioBlock: React.FC<AudioBlockProps> = ({ content, canEdit, onCapt
               onClick={() => void transcribe()}
               disabled={transcribing}
               title="In Text umwandeln (eigene Spracherkennung)"
-              className="btn-secondary h-11 sm:h-8 px-2.5 text-xs flex items-center gap-1.5 shrink-0 disabled:opacity-40"
+              className="btn-secondary !rounded-full h-11 sm:h-8 px-3 text-xs flex items-center gap-1.5 shrink-0 disabled:opacity-40"
             >
               {transcribing ? <Loader2 className="w-3.5 h-3.5 animate-spin" /> : <Wand2 className="w-3.5 h-3.5" />}
               <span className="hidden sm:inline">{transcribing ? 'Wird erkannt…' : 'Transkribieren'}</span>
@@ -107,7 +107,7 @@ export const AudioBlock: React.FC<AudioBlockProps> = ({ content, canEdit, onCapt
           )}
         </div>
       ) : (
-        <div className="flex items-center h-12 px-3 rounded-card border border-border bg-panel w-64">
+        <div className="flex items-center h-12 px-4 rounded-full border border-border bg-panel w-64">
           <Loader2 className="w-4 h-4 animate-spin text-muted" />
         </div>
       )}

frontend/src/features/workspace/AudioRecorderPicker.tsx

@@ -108,7 +108,7 @@ export const AudioRecorderPicker: React.FC<AudioRecorderPickerProps> = ({ docId,
           cancel();
         }
       }}
-      className="my-1 inline-flex max-w-full flex-col gap-2 rounded-card border border-border bg-panel-elevated px-3 py-2 focus:outline-none"
+      className="my-1 inline-flex max-w-full flex-col gap-2 rounded-3xl border border-border bg-panel-elevated px-4 py-2 focus:outline-none"
     >
       <div className="flex items-center gap-3">
         {state === 'recording' && (
@@ -162,7 +162,7 @@ export const AudioRecorderPicker: React.FC<AudioRecorderPickerProps> = ({ docId,
           onClick={cancel}
           disabled={state === 'uploading'}
           title="Abbrechen (Esc)"
-          className="w-11 h-11 sm:w-7 sm:h-7 flex items-center justify-center rounded-btn text-muted hover:text-main hover:bg-panel shrink-0 disabled:opacity-40"
+          className="w-11 h-11 sm:w-7 sm:h-7 flex items-center justify-center rounded-full text-muted hover:text-main hover:bg-panel shrink-0 disabled:opacity-40"
         >
           <X className="w-4 h-4" />
         </button>

frontend/src/features/workspace/CodeBlockEditor.tsx

@@ -1,6 +1,6 @@
 import React, { useState, useEffect, useLayoutEffect, useMemo, useRef, useCallback } from 'react';
 import Prism from 'prismjs';
-import { Code, Copy, Check } from 'lucide-react';
+import { Copy, Check } from 'lucide-react';
 import { DocumentBlock } from '../../lib/types';
 
 Prism.manual = true;
@@ -311,6 +311,7 @@ export interface CodeBlockEditorProps {
   registerTextareaRef?: (blockId: string, el: HTMLTextAreaElement | null) => void;
   onChangeContent?: (content: string) => void;
   onChangeLang?: (lang: string) => void;
+  /** Kept for callers; converting back to text lives in the bullet's action bubble now */
   onConvertToText?: () => void;
   handleFocus?: (e: React.FocusEvent<HTMLTextAreaElement>) => void;
   handleBlur?: (e: React.FocusEvent<HTMLTextAreaElement>) => void;
@@ -326,7 +327,6 @@ export const CodeBlockEditor: React.FC<CodeBlockEditorProps> = ({
   registerTextareaRef,
   onChangeContent,
   onChangeLang,
-  onConvertToText,
   handleFocus,
   handleBlur,
   handleContentChange,
@@ -542,17 +542,15 @@ export const CodeBlockEditor: React.FC<CodeBlockEditorProps> = ({
   const hasCustomUnknownLang = Boolean(selectValue && !KNOWN_OPTION_IDS.has(selectValue));
 
   return (
-    <div className="bg-code border border-border rounded-btn my-0.5 max-w-full overflow-hidden">
-      {/* Code Block Header */}
-      <div className="flex items-center justify-between gap-2 px-2 py-1 border-b border-border text-[11px] font-mono text-faint">
-        <div className="flex items-center gap-1.5 min-w-0">
-          <Code className="w-3.5 h-3.5 text-muted shrink-0" />
+    <div className="group/code relative bg-code rounded-2xl my-0.5 max-w-full overflow-hidden">
+      {/* Language at the top left; no header bar */}
+      <div className="flex items-center px-1.5 pt-1 text-[11px] font-mono text-faint">
         {canEdit ? (
           <select
             aria-label="Sprache auswählen"
             value={selectValue}
             onChange={(e) => onChangeLang?.(e.target.value)}
-              className="min-h-[44px] sm:min-h-0 bg-transparent text-muted hover:text-main focus:text-main font-mono text-[11px] font-medium border border-transparent hover:border-border focus:border-accent rounded-btn px-1.5 py-0.5 outline-none cursor-pointer"
+            className="min-h-[44px] sm:min-h-0 bg-transparent text-faint hover:text-main focus:text-main font-mono text-[11px] font-medium border border-transparent hover:border-border focus:border-accent rounded-btn px-1 py-0.5 outline-none cursor-pointer"
           >
             <option value="" className="bg-panel text-main">
               Text
@@ -573,42 +571,21 @@ export const CodeBlockEditor: React.FC<CodeBlockEditorProps> = ({
             ))}
           </select>
         ) : (
-            <span className="font-mono text-[11px] text-muted px-1">{block.lang || 'Text'}</span>
+          <span className="font-mono text-[11px] text-faint px-1">{block.lang || 'Text'}</span>
         )}
       </div>
 
-        <div className="flex items-center gap-1.5 shrink-0">
+      {/* Copy: round icon button at the bottom right, shown on hover (always on touch screens) */}
       <button
         type="button"
         onClick={handleCopy}
-            className="min-h-[44px] sm:min-h-0 px-2 py-0.5 rounded-btn text-[11px] font-mono text-muted hover:text-main hover:bg-panel-elevated transition-colors inline-flex items-center gap-1 cursor-pointer"
-            title="In die Zwischenablage kopieren"
+        className="absolute bottom-2 right-2 z-10 h-9 w-9 sm:h-8 sm:w-8 rounded-full bg-panel border border-border shadow-panel flex items-center justify-center text-muted hover:text-main opacity-100 sm:opacity-0 sm:group-hover/code:opacity-100 focus-visible:opacity-100 transition-opacity cursor-pointer"
+        title={copied ? 'Kopiert!' : 'In die Zwischenablage kopieren'}
+        aria-label={copied ? 'Kopiert!' : 'Kopieren'}
       >
-            {copied ? (
-              <>
-                <Check className="w-3 h-3 text-status-ok" />
-                <span className="text-status-ok">Kopiert!</span>
-              </>
-            ) : (
-              <>
-                <Copy className="w-3 h-3 opacity-75" />
-                <span>Kopieren</span>
-              </>
-            )}
+        {copied ? <Check className="w-3.5 h-3.5 text-status-ok" /> : <Copy className="w-3.5 h-3.5" />}
       </button>
 
-          {canEdit && onConvertToText && (
-            <button
-              type="button"
-              onClick={onConvertToText}
-              className="min-h-[44px] sm:min-h-0 px-2 py-0.5 rounded-btn text-[11px] font-mono text-muted hover:text-accent hover:bg-panel-elevated transition-colors inline-flex items-center cursor-pointer"
-            >
-              Als Text
-            </button>
-          )}
-        </div>
-      </div>
-
       {/* Live Highlighted Overlay + Textarea with Line Numbers */}
       <div className="flex relative w-full overflow-hidden">
         {/* Line Numbers Column */}
@@ -618,7 +595,7 @@ export const CodeBlockEditor: React.FC<CodeBlockEditorProps> = ({
           onScroll={handleLineNumbersScroll}
           onWheel={handleLineNumbersWheel}
           data-testid="code-line-numbers"
-          className="select-none py-2 pl-2.5 pr-2 font-mono text-xs text-faint leading-relaxed text-right border-r border-border/40 shrink-0 overflow-hidden"
+          className="select-none py-2 pl-2.5 pr-2 font-mono text-xs text-faint leading-relaxed text-right shrink-0 overflow-hidden"
         >
           {Array.from({ length: lineCount }, (_, i) => (
             <div key={i + 1} data-line-number={i + 1}>

frontend/src/features/workspace/DictationBlock.tsx

@@ -85,7 +85,7 @@ export const DictationBlock: React.FC<DictationBlockProps> = ({ onDone, onCancel
       }}
       disabled={transcribing || !!error}
       aria-label="Diktat beenden"
-      className="relative w-full min-h-[56px] sm:min-h-[44px] my-1 px-3 py-2 rounded-card border border-accent bg-accent-dim overflow-hidden flex flex-col gap-1.5 text-left cursor-pointer disabled:cursor-default focus:outline-none"
+      className="relative w-full min-h-[56px] sm:min-h-[44px] my-1 px-4 py-2 rounded-3xl border border-accent bg-accent-dim overflow-hidden flex flex-col gap-1.5 text-left cursor-pointer disabled:cursor-default focus:outline-none"
     >
       {(interim || chunkBusy) && !error && (
         <div className="w-full text-sm text-main whitespace-pre-wrap break-words leading-relaxed pointer-events-none">

frontend/src/features/workspace/OutlinerBlock.tsx

@@ -1613,8 +1613,8 @@ export const OutlinerBlock: React.FC<OutlinerBlockProps> = ({
             : 'opacity-0 group-hover:opacity-100 focus-within:opacity-100 pointer-events-none group-hover:pointer-events-auto focus-within:pointer-events-auto'
         }`}
       >
-        {/* Convert back to bullet for headings, callouts, divider */}
-        {canEdit && ['callout', 'h1', 'h2', 'h3', 'divider'].includes(block.type) && (
+        {/* Convert back to bullet for headings, callouts, dividers, code and numbered items */}
+        {canEdit && ['callout', 'h1', 'h2', 'h3', 'divider', 'code', 'numbered'].includes(block.type) && (
           <button
             type="button"
             onClick={() => {

frontend/src/features/workspace/__tests__/CodeBlockEditor.test.tsx

@@ -77,19 +77,14 @@ describe('CodeBlockEditor', () => {
     expect(updates[0].lang).toBe('yaml');
     expect(select.value).toBe('yaml');
 
-    // "Als Text" converts the code block back to a bullet
-    fireEvent.click(screen.getByRole('button', { name: 'Als Text' }));
-    expect(updates[updates.length - 1]?.type).toBe('bullet');
-
     unmount();
 
-    // Reader view (!canEdit): shows plain text instead of <select> and hides "Als Text"
+    // Reader view (!canEdit): shows plain text instead of <select> 
     const readerView = render(
       <CodeBlockEditor block={makeCodeBlock({ lang: 'yaml' })} canEdit={false} />
     );
     expect(readerView.container.querySelector('select')).toBeNull();
     expect(readerView.getByText('yaml')).toBeTruthy();
-    expect(readerView.queryByText('Als Text')).toBeNull();
   });
 
   it('copies the code content to the clipboard and shows "Kopiert!" for 1.5s', () => {
@@ -108,14 +103,14 @@ describe('CodeBlockEditor', () => {
     fireEvent.click(copyBtn);
 
     expect(writeTextMock).toHaveBeenCalledWith('echo "hello world"');
-    expect(screen.getByText('Kopiert!')).toBeTruthy();
+    expect(screen.getByRole('button', { name: 'Kopiert!' })).toBeTruthy();
 
     act(() => {
       vi.advanceTimersByTime(1500);
     });
 
-    expect(screen.queryByText('Kopiert!')).toBeNull();
-    expect(screen.getByText('Kopieren')).toBeTruthy();
+    expect(screen.queryByRole('button', { name: 'Kopiert!' })).toBeNull();
+    expect(screen.getByRole('button', { name: 'Kopieren' })).toBeTruthy();
   });
 
   it('indents by 2 spaces on Tab and outdents on Shift+Tab without indenting the bullet', () => {