fix(dashboard): preserve cancelled request count

frontend/src/features/dashboard/schemas.test.ts

@@ -57,6 +57,7 @@ describe("DashboardOverviewSchema", () => {
           cachedInputTokens: 300,
           errorRate: 0.02,
           errorCount: 10,
+          cancelledCount: 3,
           topError: null,
         },
         comparison: {
@@ -81,6 +82,7 @@ describe("DashboardOverviewSchema", () => {
 
     expect(parsed.accounts).toHaveLength(0);
     expect(parsed.summary.comparison?.previous.requests).toBe(250);
+    expect(parsed.summary.metrics?.cancelledCount).toBe(3);
   });
 
   it("drops legacy request_logs field from parse result", () => {

frontend/src/features/dashboard/schemas.ts

@@ -64,6 +64,7 @@ const DashboardMetricsSchema = z.object({
   cachedInputTokens: z.number().nullable(),
   errorRate: z.number().nullable(),
   errorCount: z.number().nullable(),
+  cancelledCount: z.number().int().nonnegative().nullable().optional(),
   topError: z.string().nullable(),
   conversations: z.number().int().nullable().optional().default(null),
   conversationRequests: z.number().int().nonnegative().optional().default(0),

openspec/changes/preserve-dashboard-cancelled-count/design.md

@@ -0,0 +1,44 @@
+## Context
+
+The backend overview response already carries a nullable `cancelledCount`.
+`DashboardOverviewSchema` is the frontend trust boundary, and Zod strips
+unknown object keys there. The omission is therefore isolated to the typed
+consumer contract; no calculation or transport change is required.
+
+## Goals / Non-Goals
+
+**Goals:**
+
+- Keep the frontend overview contract aligned with the backend response.
+- Lock the documented requests/error/cancelled breakdown with a focused test.
+
+**Non-Goals:**
+
+- Change cancellation classification or aggregation.
+- Add a new dashboard card or navigation surface.
+- Change backward compatibility for payloads that omit the field.
+
+## Decisions
+
+- Declare `cancelledCount` as nullable and optional, matching the additive
+  backend response and preserving compatibility with older servers.
+- Test the field through `DashboardOverviewSchema.parse`, the actual API
+  boundary, rather than testing the nested schema in isolation.
+
+Alternative considered: configure the metrics object with `.passthrough()`.
+That would weaken the trust boundary for every unknown metric, so the explicit
+field is the smaller and safer change.
+
+## Risks / Trade-offs
+
+- [Risk] Frontend and backend optionality drift → Mirror the existing additive
+  metric pattern and cover a payload that includes the field.
+
+## Migration Plan
+
+Ship as an additive frontend contract change. Rollback is removal of the field;
+backend responses remain compatible in either direction.
+
+## Open Questions
+
+None.

openspec/changes/preserve-dashboard-cancelled-count/proposal.md

@@ -0,0 +1,28 @@
+## Why
+
+The dashboard overview API emits `cancelledCount`, but the frontend Zod
+boundary omits that field and silently strips it from otherwise valid metrics
+payloads. Operators therefore cannot distinguish a window with no
+cancellations from one whose cancellation count was discarded client-side.
+
+## What Changes
+
+- Preserve `cancelledCount` when the dashboard parses overview metrics.
+- Add a frontend contract regression covering the backend's documented
+  requests/error/cancelled breakdown.
+
+## Capabilities
+
+### New Capabilities
+
+None.
+
+### Modified Capabilities
+
+- `usage-error-metrics`: The dashboard frontend preserves the overview
+  cancellation count emitted by the API.
+
+## Impact
+
+Frontend dashboard schema and its focused tests only. No backend, database, or
+navigation changes.

openspec/changes/preserve-dashboard-cancelled-count/specs/usage-error-metrics/spec.md

@@ -0,0 +1,20 @@
+## MODIFIED Requirements
+
+### Requirement: Cancelled counts surface alongside error counts
+
+Metric surfaces that expose an error count MUST also expose the window's
+cancelled count as an additive field: the dashboard overview metrics
+(`cancelledCount`), the usage summary metrics (`cancelled7d`), the reports
+daily rows (`cancelled_count`) and summary (`total_cancelled`), and the fleet
+pressure metrics (`cancelledCount`). The dashboard overview cancelled total
+MUST be sourced from the demand quarter rollup (status grain) for the folded
+segment plus the raw tail, so it stays accurate across history already folded
+without the hourly `cancelled_count` measure. The dashboard frontend MUST
+preserve `cancelledCount` when parsing the overview response.
+
+#### Scenario: Dashboard overview preserves the status breakdown
+
+- **GIVEN** the dashboard overview API returns `requests=4`, `errorCount=1`,
+  and `cancelledCount=2`
+- **WHEN** the frontend parses the overview response
+- **THEN** the parsed metrics expose all three values unchanged

openspec/changes/preserve-dashboard-cancelled-count/tasks.md

@@ -0,0 +1,11 @@
+## 1. Frontend contract
+
+- [x] 1.1 Add a failing dashboard schema test that requires `cancelledCount`
+  to survive parsing
+- [x] 1.2 Add `cancelledCount` to the dashboard metrics Zod schema
+
+## 2. Validation
+
+- [x] 2.1 Run the focused dashboard schema tests
+- [x] 2.2 Run frontend typecheck and build
+- [x] 2.3 Validate OpenSpec