chore(ci): Remove node-overhead GitHub Action (#20246)

## Summary

- Remove the `node-overhead-gh-action` dev-package and its CI job
entirely

The node overhead check was too flaky to be reliable and was mostly
ignored in practice.

### What's removed:

- `dev-packages/node-overhead-gh-action/` — the entire action package
(16 files)
- `job_node_overhead_check` job from `.github/workflows/build.yml`
- `changed_node_overhead_action` build output variable
- Workspace entry from root `package.json`

## Test plan

- [x] No remaining references to `node-overhead` in the codebase
- [x] Workflow YAML validates correctly (24 jobs, down from 25)
- [ ] CI passes without the removed job

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-authored-by: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

Author: mydea

.github/workflows/build.yml

@@ -152,9 +152,6 @@ jobs:
       changed_node:
         ${{ needs.job_get_metadata.outputs.changed_ci == 'true' || contains(steps.checkForAffected.outputs.affected,
         '@sentry/node') }}
-      changed_node_overhead_action:
-        ${{ needs.job_get_metadata.outputs.changed_ci == 'true' || contains(steps.checkForAffected.outputs.affected,
-        '@sentry-internal/node-overhead-gh-action') }}
       changed_deno:
         ${{ needs.job_get_metadata.outputs.changed_ci == 'true' || contains(steps.checkForAffected.outputs.affected,
         '@sentry/deno') }}
@@ -208,37 +205,6 @@ jobs:
           # Only run comparison against develop if this is a PR
           comparison_branch: ${{ (github.event_name == 'pull_request' && github.base_ref) ||  ''}}
 
-  job_node_overhead_check:
-    name: Node Overhead Check
-    needs: [job_get_metadata, job_build]
-    timeout-minutes: 15
-    runs-on: ubuntu-24.04
-    if:
-      (needs.job_build.outputs.changed_node == 'true' && github.event_name == 'pull_request') ||
-      (needs.job_build.outputs.changed_node_overhead_action == 'true' && github.event_name == 'pull_request') ||
-      needs.job_get_metadata.outputs.is_base_branch == 'true' || needs.job_get_metadata.outputs.is_release == 'true'
-    steps:
-      - name: Check out current commit (${{ needs.job_get_metadata.outputs.commit_label }})
-        uses: actions/checkout@v6
-        with:
-          ref: ${{ env.HEAD_COMMIT }}
-      - name: Set up Node
-        uses: actions/setup-node@v6
-        with:
-          node-version-file: 'package.json'
-      - name: Restore caches
-        uses: ./.github/actions/restore-cache
-        with:
-          dependency_cache_key: ${{ needs.job_build.outputs.dependency_cache_key }}
-      - name: Check node overhead
-        uses: ./dev-packages/node-overhead-gh-action
-        env:
-          DEBUG: '1'
-        with:
-          github_token: ${{ secrets.GITHUB_TOKEN }}
-          # Only run comparison against develop if this is a PR
-          comparison_branch: ${{ (github.event_name == 'pull_request' && github.base_ref) ||  ''}}
-
   job_lint:
     name: Lint
     # Even though the linter only checks source code, not built code, it needs the built code in order check that all