fix(sqlite,browser): resolve SQLite connection pool deadlock, disable stale SW cache, and update BRAIN.md

frontend/src/features/capture/InstantCaptureBar.tsx

@@ -148,40 +148,46 @@ export const InstantCaptureBar: React.FC<InstantCaptureBarProps> = ({
     const effectiveTarget = overrideTarget || target;
     const effectiveListId =
       overrideListId || targetListId || (lists.length > 0 ? lists[0].id : '');
+    const capturedPriority = priority;
+    const capturedDueDate = dueDate;
+    const capturedSource = isListening ? 'voice' : 'manual';
 
+    // Optimistically clear input immediately so the UI feels instant (<10ms) in all browsers
+    setContent('');
+    setPriority('normal');
+    setDueDate('');
+    setTarget('inbox');
+    setShowOptions(false);
     setIsSubmitting(true);
     triggerHaptic(15);
 
+    const savedMsg =
+      effectiveTarget === 'task'
+        ? 'Als Aufgabe!'
+        : effectiveTarget === 'list_item'
+        ? 'Auf Liste!'
+        : effectiveTarget === 'document'
+        ? 'Als Notiz!'
+        : 'Im Dump!';
+    setJustSavedLabel(savedMsg);
+    setTimeout(() => setJustSavedLabel(null), 1600);
+    inputRef.current?.focus();
+
     try {
       const created = await api.captureThought(
         trimmed,
-        priority,
-        isListening ? 'voice' : 'manual',
-        dueDate,
+        capturedPriority,
+        capturedSource,
+        capturedDueDate,
         {
           target: effectiveTarget,
           targetListId: effectiveTarget === 'list_item' ? effectiveListId : '',
         }
       );
-      setContent('');
-      setPriority('normal');
-      setDueDate('');
-      setTarget('inbox');
-      setShowOptions(false);
-
-      const savedMsg =
-        effectiveTarget === 'task'
-          ? 'Als Aufgabe!'
-          : effectiveTarget === 'list_item'
-          ? 'Auf Liste!'
-          : effectiveTarget === 'document'
-          ? 'Als Notiz!'
-          : 'Im Dump!';
-      setJustSavedLabel(savedMsg);
-      setTimeout(() => setJustSavedLabel(null), 1600);
-
       onCaptured(created, effectiveTarget);
-      inputRef.current?.focus();
+    } catch {
+      // Restore text if capture unexpectedly failed completely
+      setContent(trimmed);
     } finally {
       setIsSubmitting(false);
     }
@@ -221,6 +227,12 @@ export const InstantCaptureBar: React.FC<InstantCaptureBarProps> = ({
             type="text"
             value={content}
             onChange={(e) => setContent(e.target.value)}
+            onKeyDown={(e) => {
+              if (e.key === 'Enter' && !e.shiftKey) {
+                e.preventDefault();
+                executeCapture();
+              }
+            }}
             placeholder={
               isListening
                 ? 'Ich höre zu…'

frontend/src/lib/api.ts

@@ -40,6 +40,7 @@ async function request<T>(path: string, options: RequestInit = {}, isRetry = fal
   const token = getToken();
   const headers: Record<string, string> = {
     'Content-Type': 'application/json',
+    'Cache-Control': 'no-cache',
     ...(options.headers as Record<string, string>),
   };
 
@@ -47,16 +48,27 @@ async function request<T>(path: string, options: RequestInit = {}, isRetry = fal
     headers['Authorization'] = `Bearer ${token}`;
   }
 
-  const res = await fetch(path, {
-    ...options,
-    headers,
-  });
+  const controller = new AbortController();
+  const timeoutId = window.setTimeout(() => controller.abort(), 8000);
+
+  let res: Response;
+  try {
+    res = await fetch(path, {
+      ...options,
+      headers,
+      cache: 'no-store',
+      signal: controller.signal,
+    });
+  } finally {
+    window.clearTimeout(timeoutId);
+  }
 
   if (res.status === 401 && !isRetry && !path.includes('/auth/login') && !path.includes('/auth/quickstart')) {
     try {
       const qsRes = await fetch('/api/v1/auth/quickstart', {
         method: 'POST',
         headers: { 'Content-Type': 'application/json' },
+        cache: 'no-store',
       });
       if (qsRes.ok) {
         const qsData = await qsRes.json();