fix: narrow provenance 404 catch, revert global log downgrade, gate empty-state on loaded id

- cardsApi.getCardProvenance: only return null for 404s whose message
  starts with "Capture provenance not found"; rethrow card-not-found 404s
  so they surface as real errors instead of silently showing manual-card
  empty state (addresses Copilot review comment)
- http.ts interceptor: revert global 404 warn downgrade — the API layer
  now handles the expected absence silently so the interceptor no longer
  needs special-casing, and downgrading all 404s globally reduces
  observability for genuine missing-resource errors (addresses Gemini
  review comment)
- CardModal.vue: gate provenance empty-state on loadedCaptureProvenanceCardId
  === card.id so the "Created manually" message does not flash for
  capture-pipeline cards while comments are being awaited before
  provenance fetch starts (addresses Copilot review comment)
- cardsApi.spec.ts: update 404 test to use the narrowed message check,
  add test for card-not-found 404 that must rethrow (1547 tests pass)

Author: Chris0Jeky

frontend/taskdeck-web/src/api/cardsApi.ts

@@ -36,9 +36,15 @@ export const cardsApi = {
       const { data } = await http.get<CardCaptureProvenance>(`/boards/${boardId}/cards/${cardId}/provenance`)
       return data
     } catch (e: unknown) {
-      const candidate = e as { response?: { status?: number } } | null
-      if (candidate?.response?.status === 404) {
-        // Manual cards have no capture provenance — treat absence as empty state, not an error.
+      const candidate = e as { response?: { status?: number; data?: { message?: string } } } | null
+      if (
+        candidate?.response?.status === 404 &&
+        typeof candidate.response.data?.message === 'string' &&
+        candidate.response.data.message.startsWith('Capture provenance not found')
+      ) {
+        // Manual cards have no capture provenance — treat only that specific absence as
+        // empty state, not an error. Other 404s (e.g. card not found in board) are rethrown
+        // so callers can surface them as genuine errors.
         return null
       }
       throw e

frontend/taskdeck-web/src/api/http.ts

@@ -45,14 +45,7 @@ http.interceptors.response.use(
   (response) => response,
   (error) => {
     if (error.response) {
-      // 404 is an expected "not found" state for optional resources (e.g. capture
-      // provenance on manually-created cards). Log at warn level so callers that
-      // handle the absence silently don't pollute the console with error noise.
-      if (error.response.status === 404) {
-        console.warn('API Not Found:', error.response.data)
-      } else {
-        console.error('API Error:', error.response.data)
-      }
+      console.error('API Error:', error.response.data)
 
       // Handle 401 - clear session and redirect to login (skip in demo mode)
       if (error.response.status === 401 && !isDemoMode) {

frontend/taskdeck-web/src/components/board/CardModal.vue

@@ -608,7 +608,7 @@ onBeforeUnmount(() => {
                   Triage run: {{ captureProvenance.triageRunId }}
                 </p>
               </div>
-              <p v-else class="text-xs text-on-surface-variant italic" data-testid="provenance-empty-state">Created manually — no capture provenance.</p>
+              <p v-else-if="loadedCaptureProvenanceCardId === card.id" class="text-xs text-on-surface-variant italic" data-testid="provenance-empty-state">Created manually — no capture provenance.</p>
             </div>
           </div>
         </div>

frontend/taskdeck-web/src/tests/api/cardsApi.spec.ts

@@ -136,15 +136,32 @@ describe('cardsApi', () => {
       expect(result).toEqual(provenance)
     })
 
-    it('should return null for manually-created cards with no capture provenance (404)', async () => {
-      const notFoundError = { response: { status: 404, data: { errorCode: 'NotFound' } } }
+    it('should return null for manually-created cards with no capture provenance (404 + provenance message)', async () => {
+      const notFoundError = {
+        response: {
+          status: 404,
+          data: { errorCode: 'NotFound', message: 'Capture provenance not found for card manual-card-1' },
+        },
+      }
       vi.mocked(http.get).mockRejectedValue(notFoundError)
 
       const result = await cardsApi.getCardProvenance('board-1', 'manual-card-1')
 
       expect(result).toBeNull()
     })
 
+    it('should rethrow 404 when the card itself is not found (card-not-found, not provenance-absent)', async () => {
+      const cardNotFoundError = {
+        response: {
+          status: 404,
+          data: { errorCode: 'NotFound', message: 'Card with ID stale-id not found in board board-1' },
+        },
+      }
+      vi.mocked(http.get).mockRejectedValue(cardNotFoundError)
+
+      await expect(cardsApi.getCardProvenance('board-1', 'stale-id')).rejects.toEqual(cardNotFoundError)
+    })
+
     it('should rethrow non-404 errors from the provenance endpoint', async () => {
       const serverError = { response: { status: 500, data: { errorCode: 'InternalError' } } }
       vi.mocked(http.get).mockRejectedValue(serverError)