Add Discord-native hybrid front-end for Jarvis (bot + bridge)

Transform isair/jarvis into a Discord-controlled voice assistant running on
the Ubuntu VNC desktop, keeping the mature ~39k-line Python brain intact.

- bot/ (Node + bun, discord.js): /자비스 slash commands (ephemeral),
  voice channel join + voice receive/playback, pluggable VNC screen broadcast
  (selfbot live / noVNC / screenshot)
- bridge/ (Python, Flask): wraps jarvis STT + run_reply_engine + Piper TTS
  behind a thin localhost HTTP API
- .env.example, scripts/ (start_bridge/start_bot/dev), README rewrite,
  docs/language-comparison.md and docs/vnc-xfce-setup.md

Language decision: hybrid (Python brain + Node/bun Discord layer) because
Discord blocks bot video; native screen broadcast only works via a Node
selfbot library.

bot/src/config.ts

@@ -0,0 +1,55 @@
+/**
+ * Centralised, typed configuration loaded from environment (.env at repo root).
+ * Nothing else in the bot reads process.env directly.
+ */
+import "dotenv/config";
+
+function req(name: string): string {
+  const v = process.env[name];
+  if (!v) throw new Error(`Missing required env var: ${name} (see .env.example)`);
+  return v;
+}
+
+function opt(name: string, fallback = ""): string {
+  return process.env[name] ?? fallback;
+}
+
+export type StreamBackend = "selfbot" | "novnc" | "screenshot" | "none";
+
+export const config = {
+  // --- Normal Discord bot (voice I/O, slash commands) ---
+  botToken: req("DISCORD_BOT_TOKEN"),
+  appId: req("DISCORD_APP_ID"),
+  guildId: req("DISCORD_GUILD_ID"),
+
+  // --- Python brain bridge ---
+  bridgeUrl: opt("BRIDGE_URL", "http://127.0.0.1:8765"),
+
+  // --- VNC screen broadcast ---
+  // selfbot   = real live "Go Live" stream via a user (burner) account token
+  // novnc     = post a noVNC web link the channel can open in a browser
+  // screenshot= periodically upload VNC screenshots
+  // none      = disable screen sharing
+  streamBackend: (opt("STREAM_BACKEND", "selfbot") as StreamBackend),
+
+  // x11grab source for the VNC display (TigerVNC runs the desktop on :1)
+  vncDisplay: opt("VNC_DISPLAY", ":1"),
+  vncResolution: opt("VNC_RESOLUTION", "1920x1080"),
+  vncFramerate: parseInt(opt("VNC_FRAMERATE", "30"), 10),
+  vncBitrateKbps: parseInt(opt("VNC_BITRATE_KBPS", "4000"), 10),
+
+  // selfbot backend (ToS-risk; use a throwaway account token, never your main)
+  selfbotToken: opt("DISCORD_SELFBOT_TOKEN"),
+
+  // novnc backend
+  novncUrl: opt("NOVNC_URL", ""),
+
+  // screenshot backend
+  screenshotIntervalSec: parseInt(opt("SCREENSHOT_INTERVAL_SEC", "5"), 10),
+
+  // --- Voice behaviour ---
+  // Min/max captured utterance bounds (ms) before forwarding to the brain.
+  silenceMs: parseInt(opt("VOICE_SILENCE_MS", "800"), 10),
+};
+
+export type AppConfig = typeof config;