Remove Iridium (demo-only) and add version display

- Remove Iridium satellite decoding feature (was placeholder/demo only)
  - Delete routes/iridium.py
  - Remove Iridium UI elements from index.html
  - Remove Iridium CSS styles
  - Remove Iridium dependencies and logger
  - Clean up SDR docstrings mentioning Iridium

- Add version number display (fixes #31)
  - Add VERSION constant to config.py
  - Add --version / -V CLI flag to intercept.py
  - Display version badge in web UI header

utils/dependencies.py

@@ -189,18 +189,6 @@ TOOL_DEPENDENCIES = {
             }
         }
     },
-    'iridium': {
-        'name': 'Iridium Monitoring',
-        'tools': {
-            'iridium-extractor': {
-                'required': False,
-                'description': 'Iridium burst extractor',
-                'install': {
-                    'manual': 'https://github.com/muccc/gr-iridium'
-                }
-            }
-        }
-    },
     'sdr_hardware': {
         'name': 'SDR Hardware Support',
         'tools': {