feat: add auto-language detection support to stt-ptt

- Add STT_LANGUAGE environment variable (default: auto)
- Modify whisper-cli call to use -l flag with language code
- Add language option to HM module (enum with 23 common languages + auto)
- Update help text to document STT_LANGUAGE variable

pkgs/stt-ptt/default.nix

@@ -19,6 +19,7 @@
 
     # Configurable via environment
     STT_MODEL="''${STT_MODEL:-$MODEL_DIR/ggml-large-v3-turbo.bin}"
+    STT_LANGUAGE="''${STT_LANGUAGE:-auto}"
     STT_NOTIFY_TIMEOUT="''${STT_NOTIFY_TIMEOUT:-3000}"
 
     NOTIFY="${libnotify}/bin/notify-send"
@@ -52,7 +53,7 @@
                     "$RM" -f "$AUDIO"
                     exit 1
                 fi
-                text=$("$WHISPER" -m "$STT_MODEL" -f "$AUDIO" -np -nt 2>/dev/null | "$TR" -d '\n' | "$SED" 's/^[[:space:]]*//;s/[[:space:]]*$//')
+                text=$("$WHISPER" -m "$STT_MODEL" -f "$AUDIO" -l "$STT_LANGUAGE" -np -nt 2>/dev/null | "$TR" -d '\n' | "$SED" 's/^[[:space:]]*//;s/[[:space:]]*$//')
                 "$RM" -f "$AUDIO"
                 [[ -n "$text" ]] && "$WTYPE" -- "$text"
             fi
@@ -62,6 +63,7 @@
             echo ""
             echo "Environment variables:"
             echo "  STT_MODEL          - Path to whisper model (default: \$XDG_DATA_HOME/stt-ptt/models/ggml-large-v3-turbo.bin)"
+            echo "  STT_LANGUAGE       - Language code or 'auto' for auto-detection (default: auto)"
             echo "  STT_NOTIFY_TIMEOUT - Notification timeout in ms (default: 3000)"
             exit 1
             ;;