refactor: Remove deprecated INTERNAL_API_PORT (ultrathin monolith cleanup)

Architecture cleanup after migration to ultrathin monolith:

- Remove INTERNAL_API_PORT from .env files (was port 8002)
- Clean up bot_main.py: remove uvicorn, Thread, run_internal_api()
- Update validate.md to check /api/telegram/health instead of port 8002
- Add deprecation notices to old Windows deployment docs
- Update docs/telegram/README.md with architecture note

The Telegram internal API is now served at /api/telegram/internal/*
on the main backend port (8000/8001) instead of separate port 8002.

Also includes: menu updates, ServerLogsView improvements, script fixes

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

start-backend.sh

@@ -12,7 +12,10 @@ source "$SCRIPT_DIR/scripts/service-helpers.sh"
 # Service configuration
 SERVICE_NAME="Unified Backend"
 PORT=8000
-LOG_FILE="/tmp/unified-backend.log"
+LOGS_DIR="$ROOT_DIR/logs"
+LOG_FILE_STDOUT="$LOGS_DIR/backend-stdout.log"
+LOG_FILE_STDERR="$LOGS_DIR/backend-stderr.log"
+LOG_FILE="$LOG_FILE_STDERR"  # Default for status/logs commands
 BACKEND_DIR="$ROOT_DIR/backend"
 VENV_DIR="$BACKEND_DIR/venv"
 ENV_FILE="$BACKEND_DIR/.env"
@@ -59,11 +62,16 @@ start_backend() {
   print_info "Starting unified backend on port $PORT..."
   cd "$BACKEND_DIR"
 
-  # Clear old log file
-  > "$LOG_FILE"
+  # Create logs directory if it doesn't exist
+  mkdir -p "$LOGS_DIR"
+
+  # Clear old log files
+  > "$LOG_FILE_STDOUT"
+  > "$LOG_FILE_STDERR"
 
   # Activate virtual environment and start uvicorn
-  nohup bash -c "source venv/bin/activate && uvicorn main:app --host 0.0.0.0 --port $PORT --reload" > "$LOG_FILE" 2>&1 &
+  # stdout → backend-stdout.log, stderr → backend-stderr.log
+  nohup bash -c "source venv/bin/activate && uvicorn main:app --host 0.0.0.0 --port $PORT --reload" > "$LOG_FILE_STDOUT" 2> "$LOG_FILE_STDERR" &
 
   BACKEND_PID=$!
   cd "$ROOT_DIR"