feat: add AMSC runway observations

frontend/lib/dashboard-types.ts

@@ -958,6 +958,12 @@ export interface AmosData {
   runway_obs?: {
     runway_pairs?: Array<[string, string]> | null;
     temperatures?: Array<[number | null, number | null]> | null;
+    point_temperatures?: Array<{
+      runway?: string | null;
+      tdz_temp?: number | null;
+      mid_temp?: number | null;
+      end_temp?: number | null;
+    }> | null;
     pressures_hpa?: Array<number | null> | null;
     wind_directions?: Array<[number, number, number] | null> | null;
     wind_speeds?: Array<[number, number, number] | null> | null;
@@ -967,6 +973,7 @@ export interface AmosData {
   observation_source?: string | null;
   observation_source_zh?: string | null;
   observation_time?: string | null;
+  observation_time_local?: string | null;
 }
 
 export interface HistoryPoint {

frontend/lib/source-freshness.ts

@@ -31,6 +31,15 @@ const DEFAULT_SOURCE_PROFILE: SourceProfile = {
 };
 
 const SOURCE_PROFILES: Record<string, SourceProfile> = {
+  amsc_awos: {
+    code: "amsc_awos",
+    label: "AMSC AWOS",
+    nativeUpdateIntervalSec: 60,
+    freshWindowSec: 180,
+    expectedGraceSec: 180,
+    staleAfterSec: 900,
+    pollIntervalSec: 60,
+  },
   amos: {
     code: "amos",
     label: "AMOS",
@@ -111,6 +120,7 @@ const SOURCE_PROFILES: Record<string, SourceProfile> = {
 function canonicalSourceCode(value?: string | null) {
   const code = normalizeObservationSourceCode(value || "metar");
   if (!code) return "metar";
+  if (code.includes("amsc")) return "amsc_awos";
   if (code.includes("amos")) return "amos";
   if (code.includes("jma")) return "jma";
   if (code.includes("fmi")) return "fmi";
@@ -207,12 +217,16 @@ export function getObservationFreshness(detail?: CityDetail | null) {
   const hasAmosRunway =
     (detail.amos?.runway_obs?.temperatures?.length || 0) > 0 ||
     (detail.amos?.runway_temps?.length || 0) > 0;
-  if (hasAmosRunway || detail.amos?.source === "amos") {
+  if (hasAmosRunway || detail.amos?.source === "amos" || detail.amos?.source === "amsc_awos") {
     return buildObservationFreshness({
       observedAt: detail.amos?.observation_time || null,
-      observedAtLocal: detail.airport_current?.obs_time || detail.current?.obs_time || null,
-      sourceCode: "amos",
-      sourceLabel: detail.amos?.source_label || "AMOS",
+      observedAtLocal:
+        detail.amos?.observation_time_local ||
+        detail.airport_current?.obs_time ||
+        detail.current?.obs_time ||
+        null,
+      sourceCode: detail.amos?.source || "amos",
+      sourceLabel: detail.amos?.source_label || (detail.amos?.source === "amsc_awos" ? "AMSC AWOS" : "AMOS"),
     });
   }
   const currentSource = canonicalSourceCode(