cleanup: remove /api/config handler (extraction #2 shadow)

recon's /api/config Flask handler (lib/api.py) is edge-shadowed since
extraction #2 — navi-config (:8422) serves the route via nginx on
navi.echo6.co. The recon-side handler is dead at the edge; remove it.

lib/deployment_config.py is KEPT: get_deployment_config() still has many
in-process consumers (lib/api.py:1237 /api/landclass has_landclass gate,
google_places.py, place_detail.py x4, offroute/router.py). Only the
/api/config HTTP handler is removed; the import at api.py:27 stays.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

lib/api.py

@@ -1263,15 +1263,6 @@ def api_landclass():
     })
 
 
-@app.route('/api/config')
-def api_config():
-    """Return deployment profile config for frontend consumption."""
-    config = get_deployment_config()
-    resp = jsonify(config)
-    resp.headers['Cache-Control'] = 'public, max-age=300'
-    return resp
-
-
 @app.route('/api/health')
 def api_health():
     """Health check endpoint for monitoring."""