Install Playwright browsers via e2e's pinned version

Running the install from the repo root let bunx float to the latest playwright,
which fetched a browser build the test runtime (playwright 1.60.0, pinned in
e2e) never looks for, so the browser scenarios failed to launch. Install from
e2e so the resolved playwright matches the one the scenarios use.

Author: RhysSullivan

.github/workflows/ci.yml

@@ -94,8 +94,12 @@ jobs:
 
       # `chromium` and the new `chromium-headless-shell` ship as separate
       # downloads; the browser-driven scenarios launch the headless shell.
+      # Install from e2e so bunx resolves ITS pinned playwright (the version the
+      # tests run against) rather than floating to the latest, which would fetch
+      # a browser build the test runtime does not look for.
       - name: Install Playwright Chromium
         run: bunx playwright install --with-deps chromium chromium-headless-shell
+        working-directory: e2e
 
       # The `local` vitest project is excluded from the default `test` chain
       # (each scenario launches its own server), so run it as its own job.