fix(FN-2364): harden diagnostics context and plugin reload imports

- Add explicit operation metadata to agent-generation and ai-session-store diagnostics for cleanup, recovery, and scheduled cleanup paths
- Extend dashboard guardrail coverage to explicitly enforce diagnostics protection for agent-generation.ts and ai-session-store.ts
- Stabilize plugin module reload imports by using temporary reload files with deterministic file URLs and cache updates
- Tighten CLI Vitest workspace cleanup to safely skip missing hidden dist directories during restore

packages/dashboard/src/agent-generation.test.ts

@@ -479,6 +479,8 @@ describe("agent-generation module", () => {
         context: expect.objectContaining({
           cleanedSessions: 1,
           cleanedRateLimits: 2,
+          ttlMs: 30 * 60 * 1000,
+          rateLimitWindowMs: 60 * 60 * 1000,
           operation: "cleanup-expired",
         }),
       });

packages/dashboard/src/agent-generation.ts

@@ -215,6 +215,8 @@ function cleanupExpiredSessions(): void {
     diagnostics.info("Cleanup completed", {
       cleanedSessions,
       cleanedRateLimits,
+      ttlMs: SESSION_TTL_MS,
+      rateLimitWindowMs: RATE_LIMIT_WINDOW_MS,
       operation: "cleanup-expired",
     });
   }

packages/dashboard/src/ai-session-store.test.ts

@@ -153,6 +153,8 @@ describe("AiSessionStore", () => {
           terminalDeleted: 2,
           orphanedDeleted: 1,
           totalDeleted: 3,
+          maxAgeMs: SESSION_CLEANUP_DEFAULT_MAX_AGE_MS,
+          operation: "cleanup-stale-sessions",
         }),
       }),
     );
@@ -228,6 +230,7 @@ describe("AiSessionStore", () => {
         message: "Scheduled cleanup failed",
         context: expect.objectContaining({
           ttlMs: 60_000,
+          operation: "scheduled-cleanup",
           error: expect.objectContaining({ message: "boom" }),
         }),
       }),
@@ -282,7 +285,10 @@ describe("AiSessionStore", () => {
         level: "info",
         scope: "ai-session-store",
         message: "Recovered stale sessions after restart",
-        context: expect.objectContaining({ recovered: 2 }),
+        context: expect.objectContaining({
+          recovered: 2,
+          operation: "recover-stale-sessions",
+        }),
       }),
     );
   });

packages/dashboard/src/ai-session-store.ts

@@ -406,7 +406,10 @@ export class AiSessionStore extends EventEmitter<AiSessionStoreEvents> {
     recovered += Number(withoutQuestion.changes ?? 0);
 
     if (recovered > 0) {
-      diagnostics.info("Recovered stale sessions after restart", { recovered });
+      diagnostics.info("Recovered stale sessions after restart", {
+        recovered,
+        operation: "recover-stale-sessions",
+      });
     }
     return recovered;
   }
@@ -478,6 +481,8 @@ export class AiSessionStore extends EventEmitter<AiSessionStoreEvents> {
       terminalDeleted,
       orphanedDeleted,
       totalDeleted,
+      maxAgeMs,
+      operation: "cleanup-stale-sessions",
     });
 
     return {
@@ -497,7 +502,10 @@ export class AiSessionStore extends EventEmitter<AiSessionStoreEvents> {
       try {
         this.cleanupStaleSessions(ttlMs);
       } catch (error) {
-        diagnostics.errorFromException("Scheduled cleanup failed", error, { ttlMs });
+        diagnostics.errorFromException("Scheduled cleanup failed", error, {
+          ttlMs,
+          operation: "scheduled-cleanup",
+        });
       }
     };
 

packages/dashboard/src/planning-flow-diagnostics-guardrail.test.ts

@@ -20,6 +20,9 @@ import { resolve } from "node:path";
 /**
  * List of AI-session modules that must use the shared diagnostics helper.
  * These modules handle AI-session flows and must not use raw console.* diagnostics.
+ *
+ * Keep `agent-generation.ts` and `ai-session-store.ts` in this list — they are
+ * long-lived generation/cleanup surfaces with historical raw-console drift.
  */
 const AI_SESSION_FLOW_MODULES = [
   "planning.ts",
@@ -75,6 +78,11 @@ function findRawConsoleCalls(
 }
 
 describe("AI-Session Diagnostics Guardrail", () => {
+  it("explicitly guards agent-generation and ai-session-store modules", () => {
+    expect(AI_SESSION_FLOW_MODULES).toContain("agent-generation.ts");
+    expect(AI_SESSION_FLOW_MODULES).toContain("ai-session-store.ts");
+  });
+
   /**
    * Test that each AI-session flow module uses the shared diagnostics helper
    * instead of raw console.* calls.