fix(ashby): fold offer id into the idempotency key when present

When application.updatedAt is present, the key ignored sibling data
fields — a candidateHire delivery carries both application and offer,
so two deliveries sharing an application snapshot could collide even
though they concern different offers. Append offer.id to the
discriminator when present; it's the only sibling object Ashby's
schema ever pairs with application.

Author: waleedlatif1

apps/sim/lib/webhooks/providers/ashby.test.ts

@@ -204,6 +204,25 @@ describe('ashbyHandler', () => {
       )
     })
 
+    it('distinguishes candidateHire deliveries sharing application id + updatedAt but differing in offer', () => {
+      const application = { id: 'app-1', status: 'Hired', updatedAt: '2026-01-01T00:00:00Z' }
+      const first = {
+        action: 'candidateHire',
+        data: { application, offer: { id: 'offer-1' } },
+      }
+      const second = {
+        action: 'candidateHire',
+        data: { application, offer: { id: 'offer-2' } },
+      }
+      expect(ashbyHandler.extractIdempotencyId!(first)).not.toBe(
+        ashbyHandler.extractIdempotencyId!(second)
+      )
+      // a genuine retry of `first` (identical offer too) still dedupes
+      expect(ashbyHandler.extractIdempotencyId!({ ...first })).toBe(
+        ashbyHandler.extractIdempotencyId!(first)
+      )
+    })
+
     it('returns null when no recognizable resource is present', () => {
       expect(ashbyHandler.extractIdempotencyId!({ action: 'ping', data: {} })).toBeNull()
       expect(ashbyHandler.extractIdempotencyId!({})).toBeNull()

apps/sim/lib/webhooks/providers/ashby.ts

@@ -50,7 +50,8 @@ export const ashbyHandler: WebhookProviderHandler = {
 
     if (application?.id) {
       const discriminator = application.updatedAt ?? buildFallbackDeliveryFingerprint(data)
-      return `ashby:${action}:${application.id}:${discriminator}`
+      const offerSuffix = offer?.id ? `:${offer.id}` : ''
+      return `ashby:${action}:${application.id}:${discriminator}${offerSuffix}`
     }
     if (offer?.id) {
       return `ashby:${action}:${offer.id}`