feat(cli): check_report names the finding that stopped the check

packages/cli/src/commands/check.test.ts

@@ -2562,6 +2562,9 @@ describe("check pipeline", () => {
       expect(reached?.message).toMatch(
         /^Check reached its --budget of 70 s while running the overlap pass .*Seconds per phase: /,
       );
+      expect(trackCheckReport).toHaveBeenCalledWith(
+        expect.objectContaining({ ok: false, stopCode: "check_budget_reached" }),
+      );
       expect(report.ok).toBe(false);
       expect(report.layout.findings.some((finding) => finding.code === "container_overflow")).toBe(
         true,
@@ -3626,6 +3629,7 @@ describe("check report telemetry", () => {
       }),
     );
     expect(report.contrast.errorCount).toBe(1);
+    expect(trackCheckReport.mock.calls[0]?.[0].stopCode).toBeUndefined();
   });
 
   it("reports zero browser samples and timings after a lint short circuit", async () => {

packages/cli/src/telemetry/events.test.ts

@@ -167,6 +167,46 @@ describe("trackCheckReport", () => {
     });
   });
 
+  it("names the finding that stopped the check, and omits it when none did", () => {
+    const props = {
+      contrastGate: false,
+      motionGate: false,
+      captionZoneGate: false,
+      frameCheckGate: false,
+      snapshotsGate: false,
+      lintErrors: 0,
+      lintWarnings: 0,
+      runtimeErrors: 1,
+      runtimeWarnings: 0,
+      layoutErrors: 0,
+      layoutWarnings: 0,
+      motionErrors: 0,
+      motionWarnings: 0,
+      contrastErrors: 0,
+      contrastWarnings: 0,
+      craftWarnings: 0,
+      launchSettleMs: 0,
+      renderReadyTimedOut: false,
+      seekLoopMs: 0,
+      contrastMs: 0,
+      gridMs: 0,
+      craftMs: 0,
+      overlapMs: 0,
+      durationSec: 0,
+      gridPoints: 0,
+      contrastPoints: 0,
+      ok: false,
+      exitCode: 1,
+    };
+    trackCheckReport({ ...props, stopCode: "media_copies_unfinished" });
+    expect(trackEvent).toHaveBeenLastCalledWith(
+      "check_report",
+      expect.objectContaining({ stop_code: "media_copies_unfinished" }),
+    );
+    trackCheckReport(props);
+    expect(trackEvent.mock.calls.at(-1)?.[1]).not.toHaveProperty("stop_code");
+  });
+
   it("omits run_id when no run ID is provided", () => {
     trackCheckReport({
       contrastGate: false,

packages/cli/src/telemetry/events.ts

@@ -1,4 +1,5 @@
 import type { BrowserInstallFacts } from "../browser/installFacts.js";
+import type { StopCode } from "../utils/checkPipeline.js";
 import type { OutputResolutionIssueKind } from "@hyperframes/core";
 import { redactTelemetryString } from "@hyperframes/core/telemetry-redaction";
 import type { SubTimelineWaitOutcome } from "@hyperframes/engine";
@@ -1193,6 +1194,7 @@ export function trackCheckReport(props: {
   contrastPoints: number;
   ok: boolean;
   exitCode: number;
+  stopCode?: StopCode;
   runId?: string;
 }): void {
   trackEvent("check_report", {
@@ -1224,6 +1226,7 @@ export function trackCheckReport(props: {
     contrast_points: props.contrastPoints,
     ok: props.ok,
     exit_code: props.exitCode,
+    ...(props.stopCode && { stop_code: props.stopCode }),
     ...runIdField(props.runId),
   });
 }

packages/cli/src/utils/checkPipeline.ts

@@ -2130,6 +2130,9 @@ function buildReport(
     contrastPoints: browser.contrastChecked,
     ok: report.ok,
     exitCode: checkExitCode(report),
+    stopCode: browser.runtimeFindings
+      .map((finding) => finding.code)
+      .find((code): code is StopCode => (STOP_CODES as readonly string[]).includes(code)),
     runId: getRunId(),
   });
   return filterComponentReport(report, options);
@@ -2264,6 +2267,13 @@ function emptyBrowserResult(): CheckBrowserResult {
   };
 }
 
+export const STOP_CODES = [
+  "media_copies_unfinished",
+  "check_budget_reached",
+  "check_runtime_failure",
+] as const;
+export type StopCode = (typeof STOP_CODES)[number];
+
 function runtimeFailure(error: unknown, code?: string): CheckFinding {
   return findingAtRoot(
     code ??