ci: use runner Chrome for headless workflows (#6967)

## Thinking Path

> - Paperclip relies on CI browser suites to protect control-plane
workflows, so a stalled browser bootstrap is a release blocker even when
app code is unchanged.
> - The failing signal on [PAPA-457](/PAP/issues/PAPA-457) was specific
to the PR e2e lane timing out before tests started, which pointed at
environment setup rather than assertions.
> - The first shell-only Chromium attempt reduced download size, but the
GitHub Actions log showed Playwright still hanging inside its install
step after the headless shell download finished.
> - That means the real problem is the Playwright browser-install path
itself on the hosted Ubuntu runner, not just the size of the downloaded
artifact.
> - GitHub's Ubuntu runners already ship Google Chrome, and Playwright
can target that binary through the `chrome` channel without downloading
its own Chromium bundle.
> - The safer workflow fix is therefore to remove the Playwright install
step from the affected headless jobs and make the Playwright configs
optionally use runner Chrome only when CI opts into it.
> - This keeps local defaults unchanged, removes the failing
browser-download dependency from CI, and preserves headless coverage for
PR, standalone e2e, and release-smoke workflows.

## What Changed

- Updated `.github/workflows/pr.yml`, `.github/workflows/e2e.yml`, and
`.github/workflows/release-smoke.yml` to stop downloading Playwright
browsers and instead verify the runner's preinstalled `google-chrome`.
- Passed `PAPERCLIP_PLAYWRIGHT_CHANNEL=chrome` into the headless PR,
standalone e2e, and release-smoke test steps so those jobs explicitly
use runner Chrome.
- Updated `tests/e2e/playwright.config.ts` and
`tests/release-smoke/playwright.config.ts` to honor
`PAPERCLIP_PLAYWRIGHT_CHANNEL` while keeping the default
local/browser-bundle behavior unchanged when the env var is absent.

## Verification

- Investigated the failed PR run log and confirmed the prior `Install
Playwright` step stalled after `chromium-headless-shell` reached 100%
download.
- `PLAYWRIGHT_BROWSERS_PATH="$(mktemp -d)"
PAPERCLIP_PLAYWRIGHT_CHANNEL=chrome PAPERCLIP_E2E_SKIP_LLM=true pnpm run
test:e2e`
Result: `7 passed (21.1s)` with an empty temporary Playwright browser
cache, proving the e2e suite runs without any Playwright browser
download when the `chrome` channel is selected.
- `git diff --check`

## Risks

- This assumes GitHub's Ubuntu runner continues to ship `google-chrome`;
if that image contract changes, these workflows would need a dedicated
Chrome install step.
- The `chrome` channel can differ slightly from Playwright-managed
Chromium, so the config gate is intentionally env-scoped to CI workflows
that need the hosted-runner path.

## Model Used

- OpenAI Codex, GPT-5-based coding agent running through Paperclip's
`codex_local` adapter with tool use, shell execution, and repository
editing enabled. The exact internal snapshot/version string is not
exposed in-session.

## Checklist

- [x] I have included a thinking path that traces from project context
to this change
- [x] I have specified the model used (with version and capability
details)
- [x] I have checked ROADMAP.md and confirmed this PR does not duplicate
planned core work
- [x] I have run tests locally and they pass
- [ ] I have added or updated tests where applicable
- [ ] If this change affects the UI, I have included before/after
screenshots
- [ ] I have updated relevant documentation to reflect my changes
- [x] I have considered and documented any risks above
- [x] I will address all Greptile and reviewer comments before
requesting merge

---------

Co-authored-by: Paperclip <noreply@paperclip.ing>

.github/workflows/e2e.yml

@@ -29,9 +29,11 @@ jobs:
 
       - run: pnpm install --frozen-lockfile
       - run: pnpm build
-      - run: npx playwright install --with-deps chromium
+      - run: google-chrome --version
 
       - name: Run e2e tests
+        env:
+          PAPERCLIP_PLAYWRIGHT_CHANNEL: "chrome"
         run: pnpm run test:e2e
 
       - uses: actions/upload-artifact@v4

.github/workflows/pr.yml

@@ -273,8 +273,11 @@ jobs:
       - name: Install dependencies
         run: pnpm install --frozen-lockfile
 
-      - name: Install Playwright
-        run: npx playwright install --with-deps chromium
+      - name: Verify runner Chrome
+        # GitHub's Ubuntu runner image already ships Google Chrome, so use that
+        # directly for the headless e2e lane instead of downloading Playwright
+        # browser bundles inside the 30 minute job budget.
+        run: google-chrome --version
 
       - name: Generate Paperclip config
         run: |
@@ -294,6 +297,7 @@ jobs:
       - name: Run e2e tests
         env:
           PAPERCLIP_E2E_SKIP_LLM: "true"
+          PAPERCLIP_PLAYWRIGHT_CHANNEL: "chrome"
         run: pnpm run test:e2e
 
       - name: Upload Playwright report

.github/workflows/release-smoke.yml

@@ -58,8 +58,10 @@ jobs:
       - name: Install dependencies
         run: pnpm install --no-frozen-lockfile
 
-      - name: Install Playwright browser
-        run: npx playwright install --with-deps chromium
+      - name: Verify runner Chrome
+        # Release smoke also runs headless on GitHub's Ubuntu image, so use the
+        # runner's preinstalled Chrome instead of a Playwright browser download.
+        run: google-chrome --version
 
       - name: Launch Docker smoke harness
         run: |
@@ -89,6 +91,7 @@ jobs:
           PAPERCLIP_RELEASE_SMOKE_BASE_URL: ${{ env.SMOKE_BASE_URL }}
           PAPERCLIP_RELEASE_SMOKE_EMAIL: ${{ env.SMOKE_ADMIN_EMAIL }}
           PAPERCLIP_RELEASE_SMOKE_PASSWORD: ${{ env.SMOKE_ADMIN_PASSWORD }}
+          PAPERCLIP_PLAYWRIGHT_CHANNEL: "chrome"
         run: pnpm run test:release-smoke
 
       - name: Capture Docker logs

tests/e2e/playwright.config.ts

@@ -8,6 +8,7 @@ import { defineConfig } from "@playwright/test";
 const PORT = Number(process.env.PAPERCLIP_E2E_PORT ?? 3199);
 const BASE_URL = `http://127.0.0.1:${PORT}`;
 const PAPERCLIP_HOME = fs.mkdtempSync(path.join(os.tmpdir(), "paperclip-e2e-home-"));
+const PLAYWRIGHT_CHANNEL = process.env.PAPERCLIP_PLAYWRIGHT_CHANNEL;
 
 export default defineConfig({
   testDir: ".",
@@ -26,7 +27,10 @@ export default defineConfig({
   projects: [
     {
       name: "chromium",
-      use: { browserName: "chromium" },
+      use: {
+        browserName: "chromium",
+        ...(PLAYWRIGHT_CHANNEL ? { channel: PLAYWRIGHT_CHANNEL } : {}),
+      },
     },
   ],
   // The webServer directive bootstraps a throwaway instance and then starts it.

tests/release-smoke/playwright.config.ts

@@ -2,6 +2,7 @@ import { defineConfig } from "@playwright/test";
 
 const BASE_URL =
   process.env.PAPERCLIP_RELEASE_SMOKE_BASE_URL ?? "http://127.0.0.1:3232";
+const PLAYWRIGHT_CHANNEL = process.env.PAPERCLIP_PLAYWRIGHT_CHANNEL;
 
 export default defineConfig({
   testDir: ".",
@@ -20,7 +21,10 @@ export default defineConfig({
   projects: [
     {
       name: "chromium",
-      use: { browserName: "chromium" },
+      use: {
+        browserName: "chromium",
+        ...(PLAYWRIGHT_CHANNEL ? { channel: PLAYWRIGHT_CHANNEL } : {}),
+      },
     },
   ],
   outputDir: "./test-results",