rebrand: rename VoiceBox to TalkBox throughout codebase

- All 'voicebox'/'Voicebox'/'VOICEBOX' strings replaced with 'talkbox'/'TalkBox'/'TALKBOX'
- Port changed from 17493 to 17494 (avoids conflict with upstream VoiceBox)
- MCP tool namespace: voicebox.* -> talkbox.*
- App bundle ID: sh.voicebox.app -> com.talkbox.app
- Binary names: voicebox-server -> talkbox-server, voicebox-mcp -> talkbox-mcp
- Docker user/group: voicebox -> talkbox
- Database: voicebox.db -> talkbox.db
- Env vars: VOICEBOX_* -> TALKBOX_*
- Asset files renamed: voicebox-logo.* -> talkbox-logo.*, etc.
- External binaries in tauri.conf.json updated to talkbox-server/talkbox-mcp

backend/tests/test_cors.py

@@ -2,7 +2,7 @@
 Tests for CORS origin restrictions.
 
 Validates that the CORS middleware only allows known local origins
-and respects the VOICEBOX_CORS_ORIGINS environment variable.
+and respects the TALKBOX_CORS_ORIGINS environment variable.
 
 Uses a minimal FastAPI app that mirrors the exact CORS configuration
 from backend/main.py, so tests run without heavy ML dependencies.
@@ -32,8 +32,8 @@ def _build_app(env_origins: str = "") -> FastAPI:
     _default_origins = [
         "http://localhost:5173",
         "http://127.0.0.1:5173",
-        "http://localhost:17493",
-        "http://127.0.0.1:17493",
+        "http://localhost:17494",
+        "http://127.0.0.1:17494",
         "tauri://localhost",
         "https://tauri.localhost",
     ]
@@ -88,8 +88,8 @@ class TestCORSDefaultOrigins:
     @pytest.mark.parametrize("origin", [
         "http://localhost:5173",
         "http://127.0.0.1:5173",
-        "http://localhost:17493",
-        "http://127.0.0.1:17493",
+        "http://localhost:17494",
+        "http://127.0.0.1:17494",
         "tauri://localhost",
         "https://tauri.localhost",
     ])
@@ -121,7 +121,7 @@ class TestCORSDefaultOrigins:
 
 
 class TestCORSCustomOrigins:
-    """VOICEBOX_CORS_ORIGINS env var should extend the allowlist."""
+    """TALKBOX_CORS_ORIGINS env var should extend the allowlist."""
 
     def test_custom_origin_allowed(self, client_with_custom_origins):
         headers = _get_with_origin(client_with_custom_origins, "https://custom.example.com")
@@ -141,7 +141,7 @@ class TestCORSCustomOrigins:
 
 
 class TestCORSEnvVarParsing:
-    """Edge cases for VOICEBOX_CORS_ORIGINS parsing."""
+    """Edge cases for TALKBOX_CORS_ORIGINS parsing."""
 
     def test_empty_env_var(self):
         app = _build_app("")