Authenticate ripgrep install in CI

Pass the read-only GitHub Actions token to root bun install steps so @vscode/ripgrep postinstall can query GitHub release metadata without hitting unauthenticated API limits.

Author: jatmn

.github/workflows/pr-checks.yml

@@ -38,6 +38,8 @@ jobs:
 
       - name: Install dependencies
         run: bun install --frozen-lockfile
+        env:
+          GITHUB_TOKEN: ${{ github.token }}
 
       - name: Smoke check
         run: bun run smoke

.github/workflows/release.yml

@@ -58,6 +58,8 @@ jobs:
 
       - name: Install dependencies
         run: bun install --frozen-lockfile
+        env:
+          GITHUB_TOKEN: ${{ github.token }}
 
       - name: Run unit tests
         run: bun test --max-concurrency=1