feat(env): Phase 2.6 FIRMS adapter emits Events to pipeline bus

Second adapter wired to the new pipeline (after NWS). Reuses the
store-side emission logic added in the NWS commit.

- FIRMSAdapter.to_event() maps stored dict to pipeline Event.
- Category decision: new_ignition vs wildfire_proximity based on
  properties.new_ignition (computed by FIRMS during ingest from
  proximity to known fires).
- Severity passes through (FIRMS already pre-maps to our 3-level
  system during _parse_csv).
- group_key and inhibit_keys use a spatial grid key
  (firms:LAT:LON rounded to 0.01 degrees, ~1km) so repeated
  satellite detections of the same hotspot are coalesced and
  lower-severity re-detections are inhibited.
- Summary text enriched with FRP, confidence, and distance from
  the nearest region anchor when present.
- 13 tests covering category decision, severity pass-through,
  spatial grouping, and defensive handling of incomplete dicts.

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

meshai/env/firms.py

@@ -3,10 +3,12 @@
 import json
 import logging
 import time
-from typing import TYPE_CHECKING
+from typing import TYPE_CHECKING, Optional
 from urllib.error import HTTPError, URLError
 from urllib.request import Request, urlopen
 
+from meshai.notifications.events import Event, make_event
+
 if TYPE_CHECKING:
     from ..config import FIRMSConfig
 
@@ -342,6 +344,62 @@ class FIRMSAdapter:
 
         return (None, None)
 
+    def to_event(self, evt: dict) -> Optional["Event"]:
+        """Translate a stored FIRMS event dict into a pipeline Event.
+
+        Args:
+            evt: Internal event dict from get_events()
+
+        Returns:
+            Event instance ready for EventBus emission, or None if
+            the dict is missing required fields (lat/lon).
+        """
+        try:
+            lat = evt.get("lat")
+            lon = evt.get("lon")
+            if lat is None or lon is None:
+                return None  # Can't make a useful Event without coords
+
+            props = evt.get("properties", {}) or {}
+            is_new_ignition = bool(props.get("new_ignition", False))
+            category = "new_ignition" if is_new_ignition else "wildfire_proximity"
+
+            severity = evt.get("severity", "routine")
+
+            title = evt.get("headline", "") or "Fire Hotspot"
+
+            # Build a richer summary including FRP, confidence, distance
+            summary_parts = [title]
+            if props.get("frp") is not None:
+                summary_parts.append(f"FRP {int(props['frp'])} MW")
+            if props.get("confidence"):
+                summary_parts.append(f"conf {props['confidence']}")
+            if props.get("distance_km") is not None and props.get("nearest_anchor"):
+                summary_parts.append(
+                    f"{int(props['distance_km'])} km from {props['nearest_anchor']}"
+                )
+            summary = " | ".join(summary_parts)[:300]
+
+            spatial_key = f"firms:{round(lat, 2):.2f}:{round(lon, 2):.2f}"
+
+            return make_event(
+                source="firms",
+                category=category,
+                severity=severity,
+                title=title,
+                summary=summary,
+                timestamp=evt.get("fetched_at"),
+                expires=evt.get("expires"),
+                region=props.get("nearest_anchor"),
+                lat=lat,
+                lon=lon,
+                group_key=spatial_key,
+                inhibit_keys=[spatial_key],
+            )
+        except Exception:
+            logger.exception(f"FIRMS to_event failed for evt: {evt.get('event_id')}")
+            return None
+
     def get_events(self) -> list:
         """Get current hotspot events."""
         return self._events