cleanup: remove internal TODO from voice_routing tooltip strings (#34)

Replace phase-I-1 development placeholders in compose.voice_routing.help
(DE + EN) with user-facing descriptions of what the feature will do
when enabled. The checkbox remains disabled; only the tooltip changes.

Author: TimInTech

app/i18n.py

@@ -154,7 +154,7 @@
         "tone.neutral": "neutral",
         "tone.formal": "professionell",
         "compose.voice_routing.label": "Sprachaufnahme hierher umleiten",
-        "compose.voice_routing.help": "TODO/Future-Hook: In Phase I-1 noch nicht verdrahtet.",
+        "compose.voice_routing.help": "Sprachaufnahmen vom Hotkey direkt in dieses Entwurfsfenster leiten statt ins Hauptfenster.",
         "compose.input.label": "Entwurf",
         "compose.output.label": "Ergebnis",
         "compose.button.improve": "Verbessern",
@@ -353,7 +353,7 @@
         "tone.neutral": "neutral",
         "tone.formal": "professional",
         "compose.voice_routing.label": "Route voice input here",
-        "compose.voice_routing.help": "TODO/future hook: not wired in phase I-1 yet.",
+        "compose.voice_routing.help": "Route voice recordings from the hotkey directly into this compose window instead of the main window.",
         "compose.input.label": "Draft",
         "compose.output.label": "Result",
         "compose.button.improve": "Improve",