feat(2-C): add NIFC InciWeb wildfire narrative adapter

InciWeb adapter for RSS-based wildfire narrative updates:
- Parse DMS coordinates from description text
- Extract state name and map to 2-letter code
- Strip HTML tags and decode entities
- Bbox filtering for regional focus
- Dedup via published_ids table (14-day sweep)
- Category: fire.narrative.inciweb
- Subject: central.fire.narrative.inciweb.<state>

Includes migration 017 and 15 unit tests.

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

sql/migrations/017_add_inciweb_adapter.sql

@@ -0,0 +1,19 @@
+-- Migration: 017_add_inciweb_adapter
+-- Add InciWeb adapter to config.adapters
+-- Idempotent: uses ON CONFLICT DO NOTHING
+
+INSERT INTO config.adapters (name, enabled, cadence_s, settings)
+VALUES (
+    'inciweb',
+    false,  -- Ships disabled; operator enables via GUI
+    600,
+    jsonb_build_object(
+        'region', jsonb_build_object(
+            'north', 49.0,
+            'south', 31.0,
+            'east', -102.0,
+            'west', -124.0
+        )
+    )
+)
+ON CONFLICT (name) DO NOTHING;