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.

tests/test_frozen_env_guards.py

@@ -0,0 +1,65 @@
+"""
+Tests for frozen environment (PyInstaller) safety guards.
+
+These tests verify bundled app behaviour for stdin monitoring
+and other platform-specific guards.
+"""
+
+import sys
+from unittest.mock import patch
+
+
+class TestStdinMonitorFrozenGuard:
+    """Tests for stdin_monitor being skipped in bundled (frozen) mode.
+
+    In bundled mode (PyInstaller), sys.stdin may be devnull, so the
+    stdin_monitor thread should not start — the desktop app calls
+    request_stop() directly instead.
+    """
+
+    def test_stdin_monitor_skipped_in_frozen_mode(self):
+        """On Windows frozen apps, stdin_monitor should NOT start."""
+        with patch.object(sys, 'platform', 'win32'):
+            with patch.object(sys, 'frozen', True, create=True):
+                should_start = (
+                    sys.platform == "win32"
+                    and not getattr(sys, 'frozen', False)
+                )
+                assert should_start is False
+
+    def test_stdin_monitor_starts_in_non_frozen_mode(self):
+        """On Windows non-frozen (dev) mode, stdin_monitor should start."""
+        with patch.object(sys, 'platform', 'win32'):
+            # Remove frozen attribute if present
+            frozen_backup = getattr(sys, 'frozen', None)
+            if hasattr(sys, 'frozen'):
+                delattr(sys, 'frozen')
+            try:
+                should_start = (
+                    sys.platform == "win32"
+                    and not getattr(sys, 'frozen', False)
+                )
+                assert should_start is True
+            finally:
+                if frozen_backup is not None:
+                    sys.frozen = frozen_backup
+
+    def test_stdin_monitor_skipped_on_non_windows(self):
+        """On non-Windows platforms, stdin_monitor should not start regardless."""
+        for platform in ('darwin', 'linux'):
+            with patch.object(sys, 'platform', platform):
+                should_start = (
+                    sys.platform == "win32"
+                    and not getattr(sys, 'frozen', False)
+                )
+                assert should_start is False
+
+    def test_stdin_monitor_skipped_on_non_windows_frozen(self):
+        """On non-Windows frozen apps, stdin_monitor should not start."""
+        with patch.object(sys, 'platform', 'darwin'):
+            with patch.object(sys, 'frozen', True, create=True):
+                should_start = (
+                    sys.platform == "win32"
+                    and not getattr(sys, 'frozen', False)
+                )
+                assert should_start is False