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>

config.py

@@ -0,0 +1,97 @@
+"""Configuration settings for intercept application."""
+
+from __future__ import annotations
+
+import logging
+import os
+import sys
+
+
+def _get_env(key: str, default: str) -> str:
+    """Get environment variable with default."""
+    return os.environ.get(f'INTERCEPT_{key}', default)
+
+
+def _get_env_int(key: str, default: int) -> int:
+    """Get environment variable as integer with default."""
+    try:
+        return int(os.environ.get(f'INTERCEPT_{key}', str(default)))
+    except ValueError:
+        return default
+
+
+def _get_env_float(key: str, default: float) -> float:
+    """Get environment variable as float with default."""
+    try:
+        return float(os.environ.get(f'INTERCEPT_{key}', str(default)))
+    except ValueError:
+        return default
+
+
+def _get_env_bool(key: str, default: bool) -> bool:
+    """Get environment variable as boolean with default."""
+    val = os.environ.get(f'INTERCEPT_{key}', '').lower()
+    if val in ('true', '1', 'yes', 'on'):
+        return True
+    if val in ('false', '0', 'no', 'off'):
+        return False
+    return default
+
+
+# Logging configuration
+_log_level_str = _get_env('LOG_LEVEL', 'WARNING').upper()
+LOG_LEVEL = getattr(logging, _log_level_str, logging.WARNING)
+LOG_FORMAT = _get_env('LOG_FORMAT', '%(asctime)s - %(levelname)s - %(message)s')
+
+# Server settings
+HOST = _get_env('HOST', '0.0.0.0')
+PORT = _get_env_int('PORT', 5050)
+DEBUG = _get_env_bool('DEBUG', False)
+THREADED = _get_env_bool('THREADED', True)
+
+# Default RTL-SDR settings
+DEFAULT_GAIN = _get_env('DEFAULT_GAIN', '40')
+DEFAULT_DEVICE = _get_env('DEFAULT_DEVICE', '0')
+
+# Pager defaults
+DEFAULT_PAGER_FREQ = _get_env('PAGER_FREQ', '929.6125M')
+
+# Iridium defaults
+DEFAULT_IRIDIUM_FREQ = _get_env('IRIDIUM_FREQ', '1626.0')
+DEFAULT_IRIDIUM_SAMPLE_RATE = _get_env('IRIDIUM_SAMPLE_RATE', '2.048e6')
+
+# Timeouts
+PROCESS_TIMEOUT = _get_env_int('PROCESS_TIMEOUT', 5)
+SOCKET_TIMEOUT = _get_env_int('SOCKET_TIMEOUT', 5)
+SSE_TIMEOUT = _get_env_int('SSE_TIMEOUT', 1)
+
+# WiFi settings
+WIFI_UPDATE_INTERVAL = _get_env_float('WIFI_UPDATE_INTERVAL', 2.0)
+AIRODUMP_HEADER_LINES = _get_env_int('AIRODUMP_HEADER_LINES', 2)
+
+# Bluetooth settings
+BT_SCAN_TIMEOUT = _get_env_int('BT_SCAN_TIMEOUT', 10)
+BT_UPDATE_INTERVAL = _get_env_float('BT_UPDATE_INTERVAL', 2.0)
+
+# ADS-B settings
+ADSB_SBS_PORT = _get_env_int('ADSB_SBS_PORT', 30003)
+ADSB_UPDATE_INTERVAL = _get_env_float('ADSB_UPDATE_INTERVAL', 1.0)
+
+# Satellite settings
+SATELLITE_UPDATE_INTERVAL = _get_env_int('SATELLITE_UPDATE_INTERVAL', 30)
+SATELLITE_TRAJECTORY_POINTS = _get_env_int('SATELLITE_TRAJECTORY_POINTS', 30)
+SATELLITE_ORBIT_MINUTES = _get_env_int('SATELLITE_ORBIT_MINUTES', 45)
+
+# Maximum burst count for Iridium monitoring
+IRIDIUM_MAX_BURSTS = _get_env_int('IRIDIUM_MAX_BURSTS', 100)
+
+
+def configure_logging() -> None:
+    """Configure application logging."""
+    logging.basicConfig(
+        level=LOG_LEVEL,
+        format=LOG_FORMAT,
+        stream=sys.stderr
+    )
+    # Suppress Flask development server warning
+    logging.getLogger('werkzeug').setLevel(LOG_LEVEL)