fix(status): align stall alerts with index schedule

reference-implementations/dacs-directory/README.md

@@ -116,6 +116,8 @@ vendor directory.
 | `DACS_SCAN_MAX_TXS` | No | Maximum transactions scanned per pass; defaults to `100000` and fails closed if insufficient |
 | `DACS_SCAN_FINALITY_DEPTH` | No | Newest transaction count held back before indexing; defaults to `2` |
 | `DACS_SCAN_REPLAY_DEPTH` | No | Finalized transaction overlap replayed on every pass; defaults to `2` |
+| `DACS_INDEX_INTERVAL_SECONDS` | No | Seconds between production reindex passes; defaults to `900` |
+| `DACS_CURSOR_STALL_SECONDS` | No | Cursor-stall alert threshold; defaults to twice the valid index interval (minimum `300`, default `1800`, maximum `86400`) |
 | `DACS_RECIPE_POLICIES` | For tier elevation | JSON array of version-pinned DACS-2 recipe policies (`scheme`, `recipeVersion`, `methods`, `defaultMaxAgeSec`, `availability`, `trustedResultSigners`); absent/invalid policy fails closed to `self-declared` |
 | `DACS_TRUST_PROXY` | No | Set to `1` only behind a trusted proxy that overwrites client-IP headers; otherwise the in-process rate limiter is disabled and the deployment must enforce its edge limit |
 | `NEXT_PUBLIC_DIRECTORY_URL` | Production | Public origin used by canonical URLs, sitemap, `llms.txt`, and machine-discovery documents; defaults to `http://localhost:3400`, which silently poisons production canonical URLs and the sitemap — the server logs a warning when unset in production |

reference-implementations/dacs-directory/src/catalog/statusDiagnostics.ts

@@ -1,7 +1,9 @@
 export const DEAD_LETTER_DEFAULT_LIMIT = 20;
 export const DEAD_LETTER_MAX_LIMIT = 100;
-export const CURSOR_STALL_DEFAULT_SECONDS = 5 * 60;
+export const CURSOR_STALL_MIN_SECONDS = 5 * 60;
 export const CURSOR_STALL_MAX_SECONDS = 24 * 60 * 60;
+export const INDEX_INTERVAL_DEFAULT_SECONDS = 15 * 60;
+export const INDEX_INTERVAL_MAX_SECONDS = 12 * 60 * 60;
 
 export type StatusDiagnosticsQuery =
   | { ok: true; deadLetterLimit: number; deadLetterLocator?: string }
@@ -26,11 +28,21 @@ export function parseStatusDiagnosticsQuery(params: URLSearchParams): StatusDiag
 
 export function cursorStallThresholdSeconds(
   raw = process.env.DACS_CURSOR_STALL_SECONDS,
+  rawIndexInterval = process.env.DACS_INDEX_INTERVAL_SECONDS,
 ): number {
-  const configured = raw === undefined ? CURSOR_STALL_DEFAULT_SECONDS : Number(raw);
+  const indexInterval = Number(rawIndexInterval ?? INDEX_INTERVAL_DEFAULT_SECONDS);
+  const boundedInterval = Number.isSafeInteger(indexInterval) && indexInterval >= 1 && indexInterval <= INDEX_INTERVAL_MAX_SECONDS
+    ? indexInterval
+    : INDEX_INTERVAL_DEFAULT_SECONDS;
+  const scheduleAwareDefault = Math.min(
+    CURSOR_STALL_MAX_SECONDS,
+    Math.max(CURSOR_STALL_MIN_SECONDS, boundedInterval * 2),
+  );
+  if (raw === undefined) return scheduleAwareDefault;
+  const configured = Number(raw);
   return Number.isSafeInteger(configured) && configured >= 1 && configured <= CURSOR_STALL_MAX_SECONDS
     ? configured
-    : CURSOR_STALL_DEFAULT_SECONDS;
+    : scheduleAwareDefault;
 }
 
 export function cursorProgressDiagnostics(

reference-implementations/dacs-directory/test/dead-letter-diagnostics.test.ts

@@ -115,7 +115,11 @@ test("listing binding rejections are persistent, public-safe, filterable, and re
 test("cursor progress diagnostics distinguish caught-up, stalled, and unknown cursors", () => {
   const now = 1_000_000;
   assert.equal(cursorStallThresholdSeconds("60"), 60);
-  assert.equal(cursorStallThresholdSeconds("0"), 300);
+  assert.equal(cursorStallThresholdSeconds(undefined, "900"), 1_800);
+  assert.equal(cursorStallThresholdSeconds(undefined, "60"), 300);
+  assert.equal(cursorStallThresholdSeconds(undefined, "600"), 1_200);
+  assert.equal(cursorStallThresholdSeconds("0", "600"), 1_200);
+  assert.equal(cursorStallThresholdSeconds(undefined, "invalid"), 1_800);
   assert.deepEqual(cursorProgressDiagnostics(
     { lastSeenTxId: 10, cursorAdvancedAt: now - 61_000 },
     12,