docs: document github action learnings and add new agent rules

.agents/rules/AGENT.md

@@ -15,6 +15,7 @@ The core idea is that all feature development should take place in a dedicated b
    `git checkout main && git pull origin main && git checkout -b feature/your-feature-name`
 3. **Atomic Commits:** Make small, logical, and self-contained commits to your feature branch.
 4. **Push & Pull Request:** Push the feature branch to the remote repository and open a Pull Request (PR) against `main`. PRs act as a forum for discussing the feature and performing code reviews before it is merged.
+   - **GitHub Actions Rule:** When setting up automated workflows (like Gemini AI PR review), **always pin actions to a specific version tag** (e.g., `@v1.0.4`) instead of `@latest` to prevent breaking changes. Ensure secrets are passed safely via repository secrets (`env:`), never hardcoded.
 5. **Merge & Close:** Once approved, the feature branch is merged into `main` and then deleted. (You can use the `close_feature` skill for this).
 
 ### 2. Merge Conflict Policy
@@ -23,10 +24,26 @@ When multiple features are developed simultaneously, `main` might advance before
 #### Resolution Procedure:
 Never force-push blindly or overwrite other developers' work without understanding it. Follow these exact steps to resolve a conflict:
 
-1. **Fetch Latest Main:** Update your local repository's main branch:
+1. **Update Local Main:** Fetch the latest changes from the remote `main` branch.
    ```bash
    git checkout main
    git pull origin main
+   ```
+2. **Merge Main into Feature Branch:** Switch back to your feature branch and merge `main` into it.
+   ```bash
+   git checkout feature/your-feature-name
+   git merge main
+   ```
+3. **Resolve Conflicts:** Git will pause the merge and mark the conflicted files. Open these files in your editor, look for the conflict markers (`<<<<<<<`, `=======`, `>>>>>>>`), and manually choose the correct code. Remove the markers once done.
+4. **Stage and Commit:** After resolving all conflicts, stage the files and finish the merge commit.
+   ```bash
+   git add .
+   git commit -m "Merge main into feature and resolve conflicts"
+   ```
+5. **Push Updates:** Push the resolved feature branch back to the remote repository to update the Pull Request.
+   ```bash
+   git push origin feature/your-feature-name
+   ```
 
 ### 3. Documentation Update