fix(agents): bound media duplicate guard age

src/agents/image-generation-task-status.test.ts

@@ -378,6 +378,34 @@ describe("image generation task status", () => {
     ).toBeUndefined();
   });
 
+  it("does not keep stale recent starts forever for non-finite maxAgeMs", () => {
+    const now = Date.now();
+    recordRecentMediaGenerationTaskStartForSession({
+      sessionKey: "agent:main",
+      taskKind: IMAGE_GENERATION_TASK_KIND,
+      sourcePrefix: "image_generate",
+      taskId: "task-stale",
+      runId: "run-stale",
+      taskLabel: "stale prompt",
+      requestKey: "image-request:stale",
+      providerId: "xai",
+      progressSummary: "Generating stale image",
+      nowMs: now - 1,
+    });
+
+    expect(
+      findRecentStartedMediaGenerationTaskForSession({
+        sessionKey: "agent:main",
+        taskKind: IMAGE_GENERATION_TASK_KIND,
+        sourcePrefix: "image_generate",
+        taskLabel: "stale prompt",
+        requestKey: "image-request:stale",
+        maxAgeMs: Number.POSITIVE_INFINITY,
+        nowMs: now,
+      }),
+    ).toBeUndefined();
+  });
+
   it("does not block a distinct prompt from a cached active recent start", () => {
     recordRecentMediaGenerationTaskStartForSession({
       sessionKey: "agent:main",

src/agents/media-generation-task-status-shared.ts

@@ -1,3 +1,4 @@
+import { resolveNonNegativeIntegerOption } from "../shared/number-coercion.js";
 import {
   normalizeLowercaseStringOrEmpty,
   normalizeOptionalString,
@@ -220,7 +221,7 @@ export function findRecentStartedMediaGenerationTaskForSession(params: {
     return undefined;
   }
   const nowMs = params.nowMs ?? Date.now();
-  const maxAgeMs = Math.max(0, Math.floor(params.maxAgeMs));
+  const maxAgeMs = resolveNonNegativeIntegerOption(params.maxAgeMs, 0);
   const taskLabel = normalizeOptionalString(params.taskLabel);
   pruneRecentMediaGenerationTaskStarts({ maxAgeMs, nowMs, preserveKey: key });
   const entries = recentMediaGenerationTaskStarts.get(key);