Merge main into v4 (#2694)

Merge `main` at `734e9585` into `v4`, with conflicts resolved against
the v4 instrumentation, platform, and Vite+ refactors.
MCP tracing and LiveKit audio configuration use v4's explicit
registration paths, and the Eve and Pi fixes keep the v4
attachment-capture behavior.

Validation:
- Workspace build and type checks, lint, dead-code checks, and changeset
validation pass.
- Focused SDK and audio unit tests pass.
- All 498 tests across the seven affected e2e scenarios pass in three
consecutive cassette replay runs.
- E2e helper tests pass three times; production forwarding and generated
trace-summary links are verified against traces in `tmp-luca`.

Use a merge commit to preserve the shared history with `main`.
`v4` currently requires linear history, so that rule must be disabled
for this merge while keeping the required approval and CI checks
enabled.

---------

Co-authored-by: alexcastgonz <82875882+pcbeingused333@users.noreply.github.com>
Co-authored-by: Claude Sonnet 5.5 <noreply@anthropic.com>
Co-authored-by: David Elner <david.elner@braintrustdata.com>
Co-authored-by: github-actions[bot] <41898282+github-actions[bot]@users.noreply.github.com>
Co-authored-by: starfolkai[bot] <259249677+starfolkai[bot]@users.noreply.github.com>
Co-authored-by: Abhijeet Prasad <abhijeet@braintrustdata.com>

Author: 7 people

.changeset/livekit-audio-capture-flags.md

@@ -413,6 +413,32 @@ jobs:
         working-directory: integrations/temporal-js
         run: pnpm run test
 
+  audio:
+    runs-on: ubuntu-latest
+    timeout-minutes: 15
+    strategy:
+      fail-fast: false
+      matrix:
+        node-version: [22.18.0, 24, 26]
+    steps:
+      - uses: actions/checkout@3d3c42e5aac5ba805825da76410c181273ba90b1 # v7.0.1
+      - uses: actions/setup-node@48b55a011bda9f5d6aeb4c2d9c7362e8dae4041e # v6.4.0
+        with:
+          node-version: ${{ matrix.node-version }}
+      - name: Setup pnpm
+        uses: pnpm/action-setup@ea17c68df8912ef543352723c149a84f56e3d413 # v6.1.0
+      - name: Install dependencies
+        run: pnpm install --frozen-lockfile
+      - name: Build braintrust
+        working-directory: js
+        run: pnpm run build
+      - name: Build @braintrust/audio
+        working-directory: integrations/audio
+        run: pnpm run build
+      - name: Run @braintrust/audio tests
+        working-directory: integrations/audio
+        run: pnpm run test
+
   templates-nunjucks-js:
     runs-on: ubuntu-latest
     timeout-minutes: 15
@@ -511,6 +537,7 @@ jobs:
       - js-smoke-discover
       - js-smoke-test
       - temporal-js
+      - audio
       - templates-nunjucks-js
       - otel-js
       - js-zod-versions
@@ -544,6 +571,7 @@ jobs:
           check_result "js-smoke-discover" "${{ needs.js-smoke-discover.result }}"
           check_result "js-smoke-test" "${{ needs.js-smoke-test.result }}"
           check_result "temporal-js" "${{ needs.temporal-js.result }}"
+          check_result "audio" "${{ needs.audio.result }}"
           check_result "templates-nunjucks-js" "${{ needs.templates-nunjucks-js.result }}"
           check_result "otel-js" "${{ needs.otel-js.result }}"
           check_result "js-zod-versions" "${{ needs.js-zod-versions.result }}"

.changeset/livekit-close-waits-for-recording.md

@@ -592,6 +592,29 @@
       }
     ]
   },
+  {
+    "scenarioDirName": "mcp-instrumentation",
+    "label": "MCP Instrumentation",
+    "metadataScenario": "mcp-instrumentation",
+    "variants": [
+      {
+        "variantKey": "mcp-sdk-v1",
+        "label": "sdk v1 pinned"
+      },
+      {
+        "variantKey": "mcp-sdk-v1-latest",
+        "label": "sdk v1 latest"
+      },
+      {
+        "variantKey": "mcp-server-v2",
+        "label": "server v2 pinned"
+      },
+      {
+        "variantKey": "mcp-server-v2-latest",
+        "label": "server v2 latest"
+      }
+    ]
+  },
   {
     "scenarioDirName": "typesafe-instrumentation",
     "label": "TypeSafe Instrumentation",
@@ -777,6 +800,10 @@
         "variantKey": "eve-v0-70",
         "label": "v0.70 pinned"
       },
+      {
+        "variantKey": "eve-v0-72",
+        "label": "v0.72 pinned"
+      },
       {
         "variantKey": "eve-v0-latest",
         "label": "v0 latest"

.github/workflows/checks.yaml

@@ -6,6 +6,33 @@ describe("normalizeForSnapshot", () => {
     const media = `data:image/png;base64,${"a".repeat(3_000_000)}`;
     expect(normalizeForSnapshot(media)).toBe(media);
   });
+  test.each([0, 0.1, 1.2])(
+    "normalizes tool wall time of %s seconds",
+    (seconds) => {
+      expect(
+        normalizeForSnapshot({
+          output: {
+            structuredContent: {
+              exit_code: 0,
+              output: "pi_tool_ok",
+              truncated: false,
+              wall_time_seconds: seconds,
+            },
+          },
+        }),
+      ).toEqual({
+        output: {
+          structuredContent: {
+            exit_code: 0,
+            output: "pi_tool_ok",
+            truncated: false,
+            wall_time_seconds: 0,
+          },
+        },
+      });
+    },
+  );
+
   test("normalizes a foreign repository path ending at a workspace directory", () => {
     expect(
       normalizeForSnapshot(

e2e/config/pr-comment-scenarios.json

@@ -75,6 +75,7 @@ const ZERO_NUMBER_KEYS = new Set([
   "duration",
   "github_copilot.context_window.current",
   "time_to_first_token",
+  "wall_time_seconds",
 ]);
 const XACT_VERSION_KEYS = new Set([
   "currentVersion",

e2e/helpers/normalize.test.ts

@@ -10,6 +10,7 @@
   },
   "devDependencies": {
     "@braintrust/browser": "workspace:^",
+    "@braintrust/audio": "workspace:^",
     "@braintrust/deepseek-harness": "workspace:^",
     "@braintrust/otel": "workspace:^",
     "@braintrust/seinfeld": "workspace:^",