fix(workspace): caret at click position, no grey row highlight, hover-only collapse toggles

- Clicking into a bullet places the caret where the mouse was, mapped
  from the rendered markdown layer back to the raw text, instead of
  always jumping to the end.
- Remove the grey background on focused and hovered rows and on the
  bullet handle.
- Collapse/expand chevrons are only shown while hovering the row.

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

frontend/src/features/workspace/OutlinerBlock.tsx

@@ -72,6 +72,18 @@ export interface OutlinerBlockProps {
   onPasteMultiLines?: (blockId: string, textBefore: string, textAfter: string, rawLines: string[]) => void;
 }
 
+// Rendered markdown only drops syntax characters (**, `, [..](url) …), so its text is a subsequence of the raw
+// text. Walking both strings in parallel maps a caret offset in the rendered text back to the raw text.
+export function mapRenderedOffsetToRaw(raw: string, rendered: string, renderedOffset: number): number {
+  let j = 0;
+  for (let i = 0; i < renderedOffset && i < rendered.length; i++) {
+    const idx = raw.indexOf(rendered[i], j);
+    if (idx === -1) break;
+    j = idx + 1;
+  }
+  return Math.min(j, raw.length);
+}
+
 export const OutlinerBlock: React.FC<OutlinerBlockProps> = ({
   docId,
   block,
@@ -206,6 +218,41 @@ export const OutlinerBlock: React.FC<OutlinerBlockProps> = ({
     };
   }, []);
 
+  const renderedTextRef = useRef<HTMLSpanElement | null>(null);
+
+  // Focus the textarea and place the caret where the user clicked in the rendered (markdown) text layer
+  const focusAtPoint = (clientX: number, clientY: number) => {
+    const ta = textareaRef.current;
+    if (!ta) return;
+    const raw = ta.value;
+    let pos = raw.length;
+    const span = renderedTextRef.current;
+    const doc = document as any;
+    let node: Node | null = null;
+    let offset = 0;
+    if (typeof doc.caretPositionFromPoint === 'function') {
+      const p = doc.caretPositionFromPoint(clientX, clientY);
+      if (p) {
+        node = p.offsetNode;
+        offset = p.offset;
+      }
+    } else if (typeof doc.caretRangeFromPoint === 'function') {
+      const r = doc.caretRangeFromPoint(clientX, clientY);
+      if (r) {
+        node = r.startContainer;
+        offset = r.startOffset;
+      }
+    }
+    if (span && node && span.contains(node)) {
+      const range = document.createRange();
+      range.setStart(span, 0);
+      range.setEnd(node, offset);
+      pos = mapRenderedOffsetToRaw(raw, span.textContent || '', range.toString().length);
+    }
+    ta.focus();
+    ta.setSelectionRange(pos, pos);
+  };
+
   const adjustHeight = useCallback(() => {
     const el = textareaRef.current;
     if (!el) return;
@@ -529,9 +576,7 @@ export const OutlinerBlock: React.FC<OutlinerBlockProps> = ({
           ? 'border-t-2 border-accent bg-accent/10'
           : isTargeted
           ? 'bg-panel-elevated'
-          : activeFocus
-          ? 'bg-panel-elevated'
-          : 'hover:bg-panel'
+          : ''
       }`}
       style={{
         paddingLeft: `${visualLevel * 22 + 4}px`,
@@ -565,7 +610,7 @@ export const OutlinerBlock: React.FC<OutlinerBlockProps> = ({
             onClick={() =>
               flushDebounce(localContent, { collapsed: !block.collapsed })
             }
-            className="p-0.5 text-muted hover:text-accent transition-colors"
+            className="p-0.5 text-muted hover:text-accent transition-[color,opacity] opacity-0 group-hover:opacity-100 focus-visible:opacity-100"
             title={block.collapsed ? 'Unterpunkte ausklappen' : 'Unterpunkte einklappen'}
           >
             {block.collapsed ? (
@@ -584,7 +629,7 @@ export const OutlinerBlock: React.FC<OutlinerBlockProps> = ({
           draggable={canEdit}
           onDragStart={() => canEdit && onDragStartBlock?.(index)}
           onClick={() => onZoomBlock?.(block.id)}
-          className={`w-4 h-4 flex items-center justify-center rounded-btn hover:bg-panel-hover group/bullet transition-transform ${
+          className={`w-4 h-4 flex items-center justify-center rounded-btn group/bullet transition-transform ${
             canEdit ? 'cursor-grab active:cursor-grabbing' : 'cursor-pointer'
           }`}
           title={
@@ -682,11 +727,11 @@ export const OutlinerBlock: React.FC<OutlinerBlockProps> = ({
           <div className="relative w-full min-h-[1.5rem]">
             {/* View Layer with Inline Markdown & Actions (3-dots or Erweitert Badge) directly behind text */}
             <div
-              onClick={() => {
+              onClick={(e) => {
                 if (!activeFocus && canEdit && textareaRef.current) {
-                  textareaRef.current.focus();
-                  const len = textareaRef.current.value.length;
-                  textareaRef.current.setSelectionRange(len, len);
+                  // Keep the row's click handler from moving the caret back to the end
+                  e.stopPropagation();
+                  focusAtPoint(e.clientX, e.clientY);
                 }
               }}
               className={`w-full min-h-[1.5rem] leading-relaxed whitespace-pre-wrap break-words [overflow-wrap:anywhere] ${
@@ -704,7 +749,7 @@ export const OutlinerBlock: React.FC<OutlinerBlockProps> = ({
               }`}
             >
               {/* When actively focused, ghost text is invisible so textarea renders text/caret directly */}
-              <span className={activeFocus ? 'invisible' : ''}>
+              <span ref={renderedTextRef} className={activeFocus ? 'invisible' : ''}>
                 {localContent ? renderInlineMarkdown(localContent, { onTagClick }) : '\u200b'}
               </span>