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>

internal/api/voice.go

@@ -12,6 +12,7 @@ import (
 	"net/http"
 	"net/textproto"
 	"path"
+	"regexp"
 	"strings"
 	"sync"
 	"time"
@@ -173,6 +174,9 @@ func (s *Server) transcribe(ctx context.Context, audio []byte, filename, content
 		_ = mw.WriteField("language", lang)
 	}
 	_ = mw.WriteField("response_format", "json")
+	if s.cfg.Speech.VADFilter {
+		_ = mw.WriteField("vad_filter", "true")
+	}
 	if err := mw.Close(); err != nil {
 		return "", err
 	}
@@ -192,7 +196,62 @@ func (s *Server) transcribe(ctx context.Context, audio []byte, filename, content
 	if err := json.Unmarshal(raw, &out); err != nil {
 		return "", fmt.Errorf("unerwartete Antwort: %s", strings.TrimSpace(string(raw)))
 	}
-	return strings.TrimSpace(out.Text), nil
+	return dropRepeatedTail(strings.TrimSpace(out.Text)), nil
+}
+
+var sentenceRe = regexp.MustCompile(`[^.!?…]+[.!?…]*`)
+
+func normalizeSpeech(s string) string {
+	return strings.Trim(strings.ToLower(strings.Join(strings.Fields(s), " ")), " .,!?…;:-–")
+}
+
+// dropRepeatedTail removes what Whisper sometimes makes up at the end of longer recordings: sentences
+// it already wrote, repeated once more, or the last words echoed right after themselves.
+func dropRepeatedTail(text string) string {
+	for {
+		trimmed := dropOnce(text)
+		if trimmed == text {
+			return text
+		}
+		text = trimmed
+	}
+}
+
+func dropOnce(text string) string {
+	// Sentence level: the last k sentences occur in the same order earlier on
+	sentences := sentenceRe.FindAllStringIndex(text, -1)
+	norm := make([]string, len(sentences))
+	for i, loc := range sentences {
+		norm[i] = normalizeSpeech(text[loc[0]:loc[1]])
+	}
+	for k := len(norm) / 2; k >= 1; k-- {
+		tail := norm[len(norm)-k:]
+		if len(strings.Join(tail, " ")) < 15 {
+			continue
+		}
+		for start := 0; start+k <= len(norm)-k; start++ {
+			same := true
+			for j := 0; j < k; j++ {
+				if norm[start+j] != tail[j] || tail[j] == "" {
+					same = false
+					break
+				}
+			}
+			if same {
+				return strings.TrimSpace(text[:sentences[len(norm)-k][0]])
+			}
+		}
+	}
+	// Word level: the last n words (at least 6) directly repeat the n words before them
+	words := strings.Fields(text)
+	for n := len(words) / 2; n >= 6; n-- {
+		a := normalizeSpeech(strings.Join(words[len(words)-2*n:len(words)-n], " "))
+		b := normalizeSpeech(strings.Join(words[len(words)-n:], " "))
+		if a == b {
+			return strings.Join(words[:len(words)-n], " ")
+		}
+	}
+	return text
 }
 
 // checkVoice asks the Whisper server whether it is up and has the model.