fix(ui): SAR credential setup in Settings and async layer toggles.

Add Earthdata token entry on the SAR tab with accurate Mode B status, expose optional FIRMS_MAP_KEY in API settings, and remove the frontend operator-unlock gate that blocked localhost saves. Run network-heavy layer-enable fetches on a background executor with frontend retry polling so FIRMS toggles no longer freeze the single API worker.

backend/services/api_settings.py

@@ -78,6 +78,15 @@ API_REGISTRY = [
         "url": "https://earthquake.usgs.gov/",
         "required": False,
     },
+    {
+        "id": "firms_map_key",
+        "env_key": "FIRMS_MAP_KEY",
+        "name": "NASA FIRMS — MAP Key (optional)",
+        "description": "Optional NASA Earthdata MAP key for country-scoped VIIRS fire enrichment. Global VIIRS hotspots work without a key; set this only if you want per-country FIRMS detail. Free from NASA Earthdata.",
+        "category": "Geophysical",
+        "url": "https://firms.modaps.eosdis.nasa.gov/api/area/",
+        "required": False,
+    },
     {
         "id": "celestrak",
         "env_key": None,

backend/services/layer_enable_refresh.py

@@ -1,7 +1,8 @@
 """Immediate data refresh when the operator enables a map layer.
 
-Runs synchronously inside POST /api/layers so the frontend's post-toggle
-live-data refetch sees populated payloads (T_toggle_visible guardrail).
+Disk/local fetches run inline (milliseconds). Network-heavy fetches run on the
+slow executor so POST /api/layers never blocks the single uvicorn worker for
+tens of seconds (which freezes bootstrap + live-data and makes the map go black).
 """
 from __future__ import annotations
 
@@ -9,6 +10,15 @@ import logging
 
 logger = logging.getLogger(__name__)
 
+# Inline — local DB / static files only.
+_INSTANT_LAYER_KEYS: frozenset[str] = frozenset(
+    {"cctv", "power_plants", "datacenters"}
+)
+# Background — network-bound; may take seconds.
+_SLOW_LAYER_KEYS: frozenset[str] = frozenset(
+    {"firms", "psk_reporter", "fishing_activity"}
+)
+
 
 def snapshot_active_layers() -> dict[str, bool]:
     from services.fetchers._store import active_layers
@@ -16,26 +26,36 @@ def snapshot_active_layers() -> dict[str, bool]:
     return dict(active_layers)
 
 
-def refresh_newly_enabled_layers(before: dict[str, bool]) -> None:
-    """Fetch any layers that transitioned off → on."""
-    from services.fetchers._store import active_layers, bump_data_version
+def _was_off_now_on(before: dict[str, bool], key: str) -> bool:
+    from services.fetchers._store import active_layers
 
-    refreshed = False
+    return not bool(before.get(key, False)) and bool(active_layers.get(key, False))
 
-    def _enabled(key: str) -> bool:
-        return bool(active_layers.get(key, False))
 
-    def _was_off_now_on(key: str) -> bool:
-        return not bool(before.get(key, False)) and _enabled(key)
-
-    if _was_off_now_on("cctv"):
+def _instant_fetch(key: str) -> None:
+    if key == "cctv":
         from services.fetchers.infrastructure import fetch_cctv
 
         fetch_cctv()
-        refreshed = True
         logger.info("CCTV loaded (layer enabled)")
+        return
+    if key == "power_plants":
+        from services.fetchers.infrastructure import fetch_power_plants
 
-    if _was_off_now_on("firms"):
+        fetch_power_plants()
+        logger.info("Power plants loaded (layer enabled)")
+        return
+    if key == "datacenters":
+        from services.fetchers.infrastructure import fetch_datacenters
+
+        fetch_datacenters()
+        logger.info("Datacenters loaded (layer enabled)")
+        return
+    raise KeyError(key)
+
+
+def _slow_fetch(key: str) -> None:
+    if key == "firms":
         from services.fetchers.earth_observation import (
             fetch_firms_country_fires,
             fetch_firms_fires,
@@ -43,36 +63,61 @@ def refresh_newly_enabled_layers(before: dict[str, bool]) -> None:
 
         fetch_firms_fires()
         fetch_firms_country_fires()
-        refreshed = True
         logger.info("FIRMS fires loaded (layer enabled)")
-
-    if _was_off_now_on("power_plants"):
-        from services.fetchers.infrastructure import fetch_power_plants
-
-        fetch_power_plants()
-        refreshed = True
-        logger.info("Power plants loaded (layer enabled)")
-
-    if _was_off_now_on("psk_reporter"):
+        return
+    if key == "psk_reporter":
         from services.fetchers.infrastructure import fetch_psk_reporter
 
         fetch_psk_reporter()
-        refreshed = True
         logger.info("PSK Reporter loaded (layer enabled)")
-
-    if _was_off_now_on("datacenters"):
-        from services.fetchers.infrastructure import fetch_datacenters
-
-        fetch_datacenters()
-        refreshed = True
-        logger.info("Datacenters loaded (layer enabled)")
-
-    if _was_off_now_on("fishing_activity"):
+        return
+    if key == "fishing_activity":
         from services.fetchers.geo import fetch_fishing_activity
 
         fetch_fishing_activity()
-        refreshed = True
         logger.info("Fishing activity loaded (layer enabled)")
+        return
+    raise KeyError(key)
 
-    if refreshed:
+
+def _run_slow_enable_fetches(keys: tuple[str, ...]) -> None:
+    from services.fetchers._store import bump_data_version
+
+    for key in keys:
+        try:
+            _slow_fetch(key)
+        except Exception:
+            logger.exception("Layer enable fetch failed for %s", key)
+    bump_data_version()
+
+
+def refresh_newly_enabled_layers(before: dict[str, bool]) -> None:
+    """Fetch any layers that transitioned off → on."""
+    from services.fetchers._store import bump_data_version
+
+    instant_keys: list[str] = []
+    slow_keys: list[str] = []
+
+    for key in _INSTANT_LAYER_KEYS | _SLOW_LAYER_KEYS:
+        if _was_off_now_on(before, key):
+            if key in _INSTANT_LAYER_KEYS:
+                instant_keys.append(key)
+            else:
+                slow_keys.append(key)
+
+    if not instant_keys and not slow_keys:
+        return
+
+    for key in instant_keys:
+        try:
+            _instant_fetch(key)
+        except Exception:
+            logger.exception("Layer enable fetch failed for %s", key)
+
+    if instant_keys:
         bump_data_version()
+
+    if slow_keys:
+        from services.data_fetcher import _SLOW_EXECUTOR
+
+        _SLOW_EXECUTOR.submit(_run_slow_enable_fetches, tuple(slow_keys))

backend/services/sar/sar_config.py

@@ -167,18 +167,31 @@ def products_fetch_enabled() -> bool:
     return _flag("MESH_SAR_PRODUCTS_FETCH_ACKNOWLEDGE", default=False)
 
 
+def runtime_store_exists() -> bool:
+    """True when ``data/sar_runtime.json`` exists on disk."""
+    return _RUNTIME_FILE.is_file()
+
+
 def products_fetch_status() -> dict[str, Any]:
     """Structured status used by the router for the 'how to enable' UX."""
     raw = _str("MESH_SAR_PRODUCTS_FETCH", default="block").strip().lower()
     fetch_set = raw in {"allow", "enable", "enabled", "true", "on", "1"}
     ack_set = _flag("MESH_SAR_PRODUCTS_FETCH_ACKNOWLEDGE", default=False)
-    enabled = fetch_set and ack_set
+    token_set = bool(earthdata_token())
+    user_set = bool(earthdata_user())
+    opt_in = fetch_set and ack_set
+    # ``enabled`` historically meant opt-in flags only; ``fully_configured``
+    # is what the fetcher actually needs (flags + Earthdata token).
+    fully_configured = opt_in and token_set
     return {
-        "enabled": enabled,
+        "enabled": opt_in,
+        "fully_configured": fully_configured,
         "fetch_flag_set": fetch_set,
         "acknowledge_flag_set": ack_set,
-        "earthdata_token_set": bool(earthdata_token()),
-        "earthdata_user_set": bool(earthdata_user()),
+        "earthdata_token_set": token_set,
+        "earthdata_user_set": user_set,
+        "runtime_store_exists": runtime_store_exists(),
+        "runtime_store_path": str(_RUNTIME_FILE),
         "missing": _missing_for_products(fetch_set, ack_set),
         "help": {
             "summary": (