[Repo Assist] eng: add NuGet package cache to build, build-msix, and build-extension CI jobs

[github-actions]

🤖 This is an automated draft PR from Repo Assist.

Summary

The test CI job already uses actions/cache@v4 to cache NuGet packages, but the three downstream build jobs (build, build-msix, build-extension) each restore packages from scratch. This adds the cache step to all three.

Problem

On cold (or cache-miss) runners, each build job re-downloads the full NuGet dependency set independently:

• build (×2 for win-x64 and win-arm64): Microsoft.WindowsAppSDK, Microsoft.Windows.SDK.BuildTools, WinUIEx, etc.
• build-msix (×2): same as build
• build-extension (×2 for x64 and arm64): OpenClaw.CommandPalette dependencies

This can cost 1–3 minutes of download time per job per CI run.

Fix

Add a Cache NuGet packages step (matching the test job's pattern) to each of the three build jobs. The restore-keys: nuget-$\{\{ runner.os }}- prefix allows a cache written by the test job to be used as a warm starting point.

Cache key includes $\{\{ matrix.rid }} / $\{\{ matrix.platform }} to avoid key collisions between matrix legs while still benefiting from partial-hit fallback.

Test Status

✅ CI workflow change only — no application code modified. No test run needed. Logic verified by inspection; pattern matches the existing working cache step in the test job.

Generated by Repo Assist · ◷

To install this agentic workflow, run

gh aw add githubnext/agentics/workflows/repo-assist.md@cbb46ab386962aa371045839fc9998ee4e97ca64

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Warning

🛡️ Protected Files — Push Permission Denied

This was originally intended as a pull request, but the patch modifies protected files: .github/workflows/ci.yml.

The push was rejected because GitHub Actions does not have workflows permission to push these changes, and is never allowed to make such changes, or other authorization being used does not have this permission. A human must create the pull request manually.

To create a pull request with the changes:

# Download the patch from the workflow run
gh run download 23437978904 -n agent-artifacts -D /tmp/agent-artifacts-23437978904

# Create a new branch
git checkout -b repo-assist/eng-ci-nuget-cache-build-jobs-316d82da59e6dd30 master

# Apply the patch (--3way handles cross-repo patches)
git am --3way /tmp/agent-artifacts-23437978904/aw-repo-assist-eng-ci-nuget-cache-build-jobs.patch

# Push the branch and create the pull request
git push origin repo-assist/eng-ci-nuget-cache-build-jobs-316d82da59e6dd30
gh pr create --title '[Repo Assist] eng: add NuGet package cache to build, build-msix, and build-extension CI jobs' --base master --head repo-assist/eng-ci-nuget-cache-build-jobs-316d82da59e6dd30 --repo openclaw/openclaw-windows-node