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

CONTRIBUTING.md

@@ -1,6 +1,6 @@
-# Contributing to Voicebox
+# Contributing to TalkBox
 
-Thank you for your interest in contributing to Voicebox! This document provides guidelines and instructions for contributing.
+Thank you for your interest in contributing to TalkBox! This document provides guidelines and instructions for contributing.
 
 ## Code of Conduct
 
@@ -36,8 +36,8 @@ Thank you for your interest in contributing to Voicebox! This document provides
 Install [just](https://github.com/casey/just) (`brew install just`, `cargo install just`, or `winget install Casey.Just`), then:
 
 ```bash
-git clone https://github.com/YOUR_USERNAME/voicebox.git
-cd voicebox
+git clone https://github.com/YOUR_USERNAME/talkbox.git
+cd talkbox
 
 just setup   # creates venv, installs Python + JS deps
 just dev     # starts backend + desktop app
@@ -91,7 +91,7 @@ On Windows, to build with CUDA support for local testing:
 just build-local  # Build CPU + CUDA server binaries + Tauri installer
 ```
 
-This builds the CPU sidecar (bundled with the app), the CUDA binary (placed in `%APPDATA%/sh.voicebox.app/backends/` for runtime GPU switching), and the installable Tauri app.
+This builds the CPU sidecar (bundled with the app), the CUDA binary (placed in `%APPDATA%/sh.talkbox.app/backends/` for runtime GPU switching), and the installable Tauri app.
 
 Creates platform-specific installers (`.dmg`, `.msi`, `.AppImage`) in `tauri/src-tauri/target/release/bundle/`.
 
@@ -235,7 +235,7 @@ def create_profile(name, language):
 ## Project Structure
 
 ```
-voicebox/
+talkbox/
 ├── app/              # Shared React frontend
 │   └── src/
 │       ├── components/   # UI components
@@ -365,7 +365,7 @@ See [docs/content/docs/overview/troubleshooting.mdx](docs/content/docs/overview/
 
 - **Backend won't start:** Check Python version (3.11+), ensure venv is activated, install dependencies
 - **Tauri build fails:** Ensure Rust is installed, clean build with `cd tauri/src-tauri && cargo clean`
-- **OpenAPI client generation fails:** Ensure backend is running, check `curl http://localhost:17493/openapi.json`
+- **OpenAPI client generation fails:** Ensure backend is running, check `curl http://localhost:17494/openapi.json`
 
 ## Questions?
 
@@ -389,4 +389,4 @@ By contributing, you agree that your contributions will be licensed under the MI
 
 ---
 
-Thank you for contributing to Voicebox! 🎉
+Thank you for contributing to TalkBox! 🎉