feat: expose research truth source health identity

frontend/src/app/api/health/route.ts

@@ -1,5 +1,7 @@
 import { NextResponse } from "next/server";
 
+import { getTruthSourceRuntimeIdentity } from "@/lib/truth-source-runtime-identity";
+
 type Check = {
   status: "ok" | "degraded" | "blocked";
   message?: string;
@@ -58,12 +60,17 @@ function aggregate(checks: Record<string, Check>) {
 }
 
 export async function GET() {
+  const truthSourceIdentity = getTruthSourceRuntimeIdentity();
   const checks = {
     web: { status: "ok" } satisfies Check,
     supabasePublicConfig: envCheck(["NEXT_PUBLIC_SUPABASE_URL", "NEXT_PUBLIC_SUPABASE_ANON_KEY"]),
     supabaseServiceRole: envCheck(["SUPABASE_SERVICE_ROLE_KEY"]),
     modelProvider: anyEnvCheck(["LLM_MODELS_JSON", "OPENAI_API_KEY", "LLM_API_KEY", "DEEPSEEK_API_KEY"]),
     jyotishApi: await jyotishApiCheck(),
+    researchTruthSource: {
+      status: truthSourceIdentity.status,
+      message: truthSourceIdentity.mountStatus === "mounted" ? undefined : truthSourceIdentity.mountStatus,
+    } satisfies Check,
   };
   const status = aggregate(checks);
   return NextResponse.json(
@@ -73,6 +80,7 @@ export async function GET() {
       deployment: {
         gitCommit,
       },
+      truthSource: truthSourceIdentity,
       checks,
     },
     { status: status === "ok" ? 200 : 503 },