Repair misheard words, surface cleanup failures, add a restart action

The cleanup prompt now asks the model to fix words the transcriber misheard
when the context makes the intended one clear, and to leave them alone when
it does not. Speech models fail phonetically on proper nouns, and that is
exactly what context can recover.

The names you enter for the transcription hint are handed to the cleanup
model as a glossary too. Knowing the spelling is what lets it recognise
"kuber netis" as Kubernetes.

A failed cleanup used to be almost invisible: the raw transcript was pasted
and a progress line flashed by, so a rejected key looked exactly like
working dictation for days. It now leaves the indicator amber with the
reason, sends a notification, and records the error in the history. HTTP
401, 402 and 429 are reported as what they are, naming the service.

Also:
- Settings can test the OpenRouter key, not just the OpenAI one
- Tray menu and CLI gained Restart, which re-execs in place
- Defaults saved into the config by older versions are recognised by their
  fingerprint and dropped, so an untouched prompt keeps getting improvements
- The IPC socket is user-only; Qt puts it in /tmp

dikte.py

@@ -6,6 +6,7 @@ Usage:
   dikte.py toggle        start / stop recording
   dikte.py cancel        discard the current recording
   dikte.py settings      open the settings window
+  dikte.py restart       reload the running instance
   dikte.py quit          shut the application down
 """
 
@@ -84,6 +85,10 @@ class Dikte:
         self.settings_action = QAction(t("Settings…"), self.menu)
         self.settings_action.triggered.connect(self.open_settings)
         self.menu.addAction(self.settings_action)
+
+        self.restart_action = QAction(t("Restart"), self.menu)
+        self.restart_action.triggered.connect(self.restart)
+        self.menu.addAction(self.restart_action)
         self.menu.addSeparator()
 
         self.quit_action = QAction(t("Quit"), self.menu)
@@ -167,14 +172,25 @@ class Dikte:
         if seconds >= self.conf["max_seconds"]:
             self.stop()
 
-    def _on_recorded(self, wav_path, duration, peak):
-        self.pipeline.run(wav_path, duration, peak)
+    def _on_recorded(self, wav_path, duration, rms_values):
+        self.pipeline.run(wav_path, duration, rms_values)
 
-    def _on_finished(self, _raw, text):
-        preview = text.replace("\n", " ")
-        preview = preview[:48] + ("…" if len(preview) > 48 else "")
-        action = t("Pasted") if self.conf["auto_paste"] else t("Copied")
-        self.overlay.show_done(t("{action}: {preview}", action=action, preview=preview))
+    def _on_finished(self, _raw, text, warning):
+        if warning:
+            # The text was still pasted, but cleanup did not run. Say so loudly:
+            # a rejected key otherwise looks exactly like working dictation.
+            self.overlay.show_warning(
+                t("Pasted raw, cleanup failed: {error}", error=warning.splitlines()[0])
+            )
+            self.tray.showMessage(
+                t("Dikte: cleanup failed"), warning,
+                QSystemTrayIcon.MessageIcon.Warning, 10000,
+            )
+        else:
+            preview = text.replace("\n", " ")
+            preview = preview[:48] + ("…" if len(preview) > 48 else "")
+            action = t("Pasted") if self.conf["auto_paste"] else t("Copied")
+            self.overlay.show_done(t("{action}: {preview}", action=action, preview=preview))
         self._set_state(IDLE)
 
     def _on_error(self, message):
@@ -210,6 +226,15 @@ class Dikte:
         else:
             self.evdev.stop()
 
+    def restart(self):
+        """Replace this process with a fresh one, picking up code and settings."""
+        if self.settings_window is not None:
+            self.settings_window.close()
+        self.shutdown()
+        QLocalServer.removeServer(SERVER_NAME)
+        script = os.path.realpath(__file__)
+        os.execv(sys.executable, [sys.executable, script])
+
     def shutdown(self):
         self.evdev.stop()
         if self.state == RECORDING:
@@ -240,7 +265,8 @@ def main():
     args = [a for a in sys.argv[1:] if not a.startswith("-")]
     command = args[0] if args else ""
 
-    if command and command not in ("toggle", "cancel", "settings", "quit", "start", "stop"):
+    if command and command not in ("toggle", "cancel", "settings", "restart",
+                                   "quit", "start", "stop"):
         print(__doc__)
         return 2
 
@@ -253,7 +279,7 @@ def main():
     if send_command(command or "settings"):
         return 0
 
-    if command in ("cancel", "quit", "stop"):
+    if command in ("cancel", "quit", "stop", "restart"):
         return 0
 
     if not QSystemTrayIcon.isSystemTrayAvailable():
@@ -262,6 +288,9 @@ def main():
     dikte = Dikte(app)
 
     server = QLocalServer()
+    # Qt puts the socket in /tmp, so keep it to this user: commands like
+    # "quit" should not be reachable by anyone else on the machine.
+    server.setSocketOptions(QLocalServer.SocketOption.UserAccessOption)
     QLocalServer.removeServer(SERVER_NAME)
     if not server.listen(SERVER_NAME):
         print(f"dikte: could not open the IPC socket: {server.errorString()}")
@@ -279,6 +308,7 @@ def main():
                 "stop": dikte.stop,
                 "cancel": dikte.cancel,
                 "settings": dikte.open_settings,
+                "restart": dikte.restart,
                 "quit": app.quit,
             }.get(payload)
             if handler: