Refactor into modular structure with improvements

- Split monolithic intercept.py (15k lines) into modular structure:
  - routes/ - Flask blueprints for each feature
  - templates/ - Jinja2 HTML templates
  - data/ - OUI database, satellite TLEs, detection patterns
  - utils/ - dependencies, process management, logging
  - config.py - centralized configuration with env var support

- Add type hints to function signatures
- Replace bare except clauses with specific exceptions
- Add proper logging module (replaces print statements)
- Add environment variable support (INTERCEPT_* prefix)
- Add test suite with pytest
- Add Dockerfile for containerized deployment
- Add pyproject.toml with ruff/black/mypy config
- Add requirements-dev.txt for development dependencies

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

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

routes/sensor.py

@@ -0,0 +1,157 @@
+"""RTL_433 sensor monitoring routes."""
+
+from __future__ import annotations
+
+import json
+import queue
+import subprocess
+import threading
+from datetime import datetime
+from typing import Generator
+
+from flask import Blueprint, jsonify, request, Response
+
+import app as app_module
+from utils.logging import sensor_logger as logger
+
+sensor_bp = Blueprint('sensor', __name__)
+
+
+def stream_sensor_output(process: subprocess.Popen[bytes]) -> None:
+    """Stream rtl_433 JSON output to queue."""
+    try:
+        app_module.sensor_queue.put({'type': 'status', 'text': 'started'})
+
+        for line in iter(process.stdout.readline, b''):
+            line = line.decode('utf-8', errors='replace').strip()
+            if not line:
+                continue
+
+            try:
+                # rtl_433 outputs JSON objects, one per line
+                data = json.loads(line)
+                data['type'] = 'sensor'
+                app_module.sensor_queue.put(data)
+
+                # Log if enabled
+                if app_module.logging_enabled:
+                    try:
+                        with open(app_module.log_file_path, 'a') as f:
+                            timestamp = datetime.now().strftime('%Y-%m-%d %H:%M:%S')
+                            f.write(f"{timestamp} | {data.get('model', 'Unknown')} | {json.dumps(data)}\n")
+                    except Exception:
+                        pass
+            except json.JSONDecodeError:
+                # Not JSON, send as raw
+                app_module.sensor_queue.put({'type': 'raw', 'text': line})
+
+    except Exception as e:
+        app_module.sensor_queue.put({'type': 'error', 'text': str(e)})
+    finally:
+        process.wait()
+        app_module.sensor_queue.put({'type': 'status', 'text': 'stopped'})
+        with app_module.sensor_lock:
+            app_module.sensor_process = None
+
+
+@sensor_bp.route('/start_sensor', methods=['POST'])
+def start_sensor() -> Response:
+    with app_module.sensor_lock:
+        if app_module.sensor_process:
+            return jsonify({'status': 'error', 'message': 'Sensor already running'})
+
+        data = request.json
+        freq = data.get('frequency', '433.92')
+        gain = data.get('gain', '0')
+        ppm = data.get('ppm', '0')
+        device = data.get('device', '0')
+
+        # Clear queue
+        while not app_module.sensor_queue.empty():
+            try:
+                app_module.sensor_queue.get_nowait()
+            except queue.Empty:
+                break
+
+        # Build rtl_433 command
+        cmd = [
+            'rtl_433',
+            '-d', str(device),
+            '-f', f'{freq}M',
+            '-F', 'json'
+        ]
+
+        if gain and gain != '0':
+            cmd.extend(['-g', str(gain)])
+
+        if ppm and ppm != '0':
+            cmd.extend(['-p', str(ppm)])
+
+        full_cmd = ' '.join(cmd)
+        logger.info(f"Running: {full_cmd}")
+
+        try:
+            app_module.sensor_process = subprocess.Popen(
+                cmd,
+                stdout=subprocess.PIPE,
+                stderr=subprocess.PIPE,
+                bufsize=1
+            )
+
+            # Start output thread
+            thread = threading.Thread(target=stream_sensor_output, args=(app_module.sensor_process,))
+            thread.daemon = True
+            thread.start()
+
+            # Monitor stderr
+            def monitor_stderr():
+                for line in app_module.sensor_process.stderr:
+                    err = line.decode('utf-8', errors='replace').strip()
+                    if err:
+                        logger.debug(f"[rtl_433] {err}")
+                        app_module.sensor_queue.put({'type': 'info', 'text': f'[rtl_433] {err}'})
+
+            stderr_thread = threading.Thread(target=monitor_stderr)
+            stderr_thread.daemon = True
+            stderr_thread.start()
+
+            app_module.sensor_queue.put({'type': 'info', 'text': f'Command: {full_cmd}'})
+
+            return jsonify({'status': 'started', 'command': full_cmd})
+
+        except FileNotFoundError:
+            return jsonify({'status': 'error', 'message': 'rtl_433 not found. Install with: brew install rtl_433'})
+        except Exception as e:
+            return jsonify({'status': 'error', 'message': str(e)})
+
+
+@sensor_bp.route('/stop_sensor', methods=['POST'])
+def stop_sensor() -> Response:
+    with app_module.sensor_lock:
+        if app_module.sensor_process:
+            app_module.sensor_process.terminate()
+            try:
+                app_module.sensor_process.wait(timeout=2)
+            except subprocess.TimeoutExpired:
+                app_module.sensor_process.kill()
+            app_module.sensor_process = None
+            return jsonify({'status': 'stopped'})
+
+        return jsonify({'status': 'not_running'})
+
+
+@sensor_bp.route('/stream_sensor')
+def stream_sensor() -> Response:
+    def generate() -> Generator[str, None, None]:
+        while True:
+            try:
+                msg = app_module.sensor_queue.get(timeout=1)
+                yield f"data: {json.dumps(msg)}\n\n"
+            except queue.Empty:
+                yield f"data: {json.dumps({'type': 'keepalive'})}\n\n"
+
+    response = Response(generate(), mimetype='text/event-stream')
+    response.headers['Cache-Control'] = 'no-cache'
+    response.headers['X-Accel-Buffering'] = 'no'
+    response.headers['Connection'] = 'keep-alive'
+    return response