fix: deepen opens the linked note, task list columns in "Alle Aufgaben", Whisper repeats, date field

- The deepen buttons of task rows and Kanban cards open an already linked note (accent colour)
  instead of creating another one; the server refuses a second note for a linked task as well.
- "Alle Aufgaben" uses each task's own list columns for the status selector, dot and detail.
- Whisper: send vad_filter (STT_VAD_FILTER, default on) and drop a verbatim repeated tail of
  sentences or words from the transcript.
- Task detail: narrower time field, wider date field in the desktop sidebar.

v0.37.2.

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

frontend/src/features/triage/TasksView.tsx

@@ -355,6 +355,12 @@ export const TasksView: React.FC<TasksViewProps> = ({
     return globalColumns;
   }, [currentSelectedList, globalColumns]);
 
+  // The columns of the list a task belongs to: in "Alle Aufgaben" every task keeps its own list's columns
+  const columnsFor = (task: Thought): KanbanColumn[] => {
+    const own = safeTaskLists.find((l) => l.id === task.taskListId)?.columns;
+    return Array.isArray(own) && own.length > 0 ? own : activeColumns;
+  };
+
   const safeTasks = useMemo(() => {
     if (!Array.isArray(tasks)) return [];
     const seen = new Set<string>();
@@ -501,8 +507,9 @@ export const TasksView: React.FC<TasksViewProps> = ({
   const handleToggleDone = async (task: Thought) => {
     triggerHaptic(15);
     const nextState = !task.isCompleted;
-    const doneCol = activeColumns.find((c) => c.isDone) || activeColumns[activeColumns.length - 1];
-    const todoCol = activeColumns.find((c) => !c.isDone) || activeColumns[0];
+    const cols = columnsFor(task);
+    const doneCol = cols.find((c) => c.isDone) || cols[cols.length - 1];
+    const todoCol = cols.find((c) => !c.isDone) || cols[0];
     const nextKanban = nextState ? (doneCol ? doneCol.id : 'done') : (todoCol ? todoCol.id : 'todo');
 
     setTasks((prev) =>
@@ -516,7 +523,7 @@ export const TasksView: React.FC<TasksViewProps> = ({
 
   const handleSetKanbanStatus = async (task: Thought, nextStatus: string) => {
     triggerHaptic(15);
-    const targetCol = activeColumns.find((c) => c.id === nextStatus);
+    const targetCol = columnsFor(task).find((c) => c.id === nextStatus);
     const isCompleted = targetCol ? !!targetCol.isDone : nextStatus === 'done';
 
     setTasks((prev) =>
@@ -664,6 +671,11 @@ export const TasksView: React.FC<TasksViewProps> = ({
 
   const handleConvertToDoc = async (task: Thought) => {
     triggerHaptic(20);
+    // Already linked to a note: open it instead of creating another one
+    if (task.docId) {
+      onOpenDocument(task.docId, task.blockId);
+      return;
+    }
     const updated = await api.triageAction(task.id, 'keep', { convertTo: 'document' });
     onRefreshStats();
     // The task stays in its list, linked to the note's first checkbox (docId); open that note
@@ -1339,7 +1351,8 @@ export const TasksView: React.FC<TasksViewProps> = ({
               {/* Status: dot in the column colour; a selector on desktop, plain text on phones (changed in TaskDetailModal) */}
               {(() => {
                 const statusId = task.kanbanStatus || (isCompleted ? 'done' : 'todo');
-                const statusCol = activeColumns.find((c) => c.id === statusId);
+                const taskColumns = columnsFor(task);
+                const statusCol = taskColumns.find((c) => c.id === statusId);
                 const dot = <span className={`w-1.5 h-1.5 rounded-full flex-shrink-0 ${columnDotClass(statusCol)}`} aria-hidden="true" />;
                 return (
                   <>
@@ -1352,7 +1365,7 @@ export const TasksView: React.FC<TasksViewProps> = ({
                         className="h-5 px-1.5 text-[10px] rounded-btn border border-border bg-panel text-muted hover:text-main cursor-pointer"
                         title="Status / Zustand ändern"
                       >
-                        {activeColumns.map((c) => (
+                        {taskColumns.map((c) => (
                           <option key={c.id} value={c.id}>
                             {c.name}
                           </option>
@@ -1469,8 +1482,8 @@ export const TasksView: React.FC<TasksViewProps> = ({
             type="button"
             draggable={false}
             onClick={() => handleConvertToDoc(task)}
-            title="Als Notiz vertiefen"
-            className="text-faint hover:text-accent p-1.5 transition-colors hidden sm:block"
+            title={task.docId ? 'Verknüpfte Notiz öffnen' : 'Als Notiz vertiefen'}
+            className={`${task.docId ? 'text-accent' : 'text-faint'} hover:text-accent p-1.5 transition-colors hidden sm:block`}
           >
             <FileText className="w-3.5 h-3.5" />
           </button>
@@ -2292,7 +2305,7 @@ export const TasksView: React.FC<TasksViewProps> = ({
           setShowDetailModal(false);
           setDetailTaskId(null);
         }}
-        activeColumns={activeColumns}
+        activeColumns={detailTask ? columnsFor(detailTask) : activeColumns}
         taskLists={safeTaskLists}
         onOpenDocument={onOpenDocument}
         onUpdateTitle={handleUpdateTaskTitle}
@@ -2412,8 +2425,8 @@ export const TasksView: React.FC<TasksViewProps> = ({
                           <div className="hidden sm:flex items-center gap-1 flex-shrink-0" onClick={(e) => e.stopPropagation()}>
                             <button
                               onClick={() => handleConvertToDoc(task)}
-                              title="Als Notiz vertiefen"
-                              className="text-faint hover:text-accent p-0.5"
+                              title={task.docId ? 'Verknüpfte Notiz öffnen' : 'Als Notiz vertiefen'}
+                              className={`${task.docId ? 'text-accent' : 'text-faint'} hover:text-accent p-0.5`}
                             >
                               <FileText className="w-3.5 h-3.5" />
                             </button>