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

tauri/src-tauri/src/focus_capture.rs

@@ -25,8 +25,8 @@
 //!
 //! PID + bundle id + role are all captured for diagnostics — the bundle
 //! id lets step 6 (internal direct injection) detect "focus was inside
-//! Voicebox itself" and short-circuit the synthetic-paste path. On
-//! Windows, `bundle_id` holds the lowercased exe basename (`"voicebox.exe"`)
+//! TalkBox itself" and short-circuit the synthetic-paste path. On
+//! Windows, `bundle_id` holds the lowercased exe basename (`"talkbox.exe"`)
 //! since there's no equivalent of macOS' reverse-DNS bundle identifier.
 
 #[derive(Debug, Clone, serde::Serialize, serde::Deserialize)]
@@ -350,7 +350,7 @@ mod win {
     }
 
     /// Query a PID's executable path and return its lowercased basename
-    /// (e.g. `"voicebox.exe"`). This is the Windows analogue of macOS'
+    /// (e.g. `"talkbox.exe"`). This is the Windows analogue of macOS'
     /// `bundleIdentifier`, just less globally unique — two apps with the
     /// same exe name can collide, but that's rare enough to accept for
     /// the self-paste short-circuit.