feat: pnpm defaults [INFRA-77654] (#12)

* feat: throttle re-runs [INFRA-77654]

* pnpm defaults

* more support for getting to implicit pnpm version

* optional merges

* style: format code with prettier

- Remove leading blank line
- Convert single quotes to double quotes
- Add trailing commas to function parameters and arrays
- Format multi-line function parameters
- Consistent spacing and indentation

* feat: enable GitHub auto-merge for PRs

- Try to enable auto-merge via GitHub API when merge=true
- Fall back to manual merge if auto-merge fails or is not available
- Only perform manual merge if auto-merge was not successfully enabled
- Update log message to clarify when merge is manual vs auto

This allows GitHub to automatically merge PRs when they become ready
(CI passes, approval requirements met), reducing the need for manual
intervention or periodic script re-runs.

Author: ahammond

CLAUDE.md

@@ -0,0 +1,101 @@
+# CLAUDE.md
+
+This file provides guidance to Claude Code (claude.ai/code) when working with code in this repository.
+
+## Project Overview
+
+This is an Octoherd script that automates the merging of Renovate dependency update PRs across multiple repositories. It's designed to handle major version library updates, "all non-major updates" PRs, and projen update PRs.
+
+## Key Commands
+
+### Running the Script
+```bash
+# Basic usage
+node cli.js \
+  -R time-loop/*-cdk \
+  -T ghp_TOKEN \
+  --majorVersion v11
+
+# Handle "all non-major updates" PRs
+node cli.js \
+  -R time-loop/*-cdk \
+  -T ghp_TOKEN \
+  --majorVersion all
+
+# Handle projen update PRs
+node cli.js \
+  -R time-loop/*-cdk \
+  -T ghp_TOKEN \
+  --majorVersion projen
+```
+
+### Testing
+```bash
+npm test  # Alias for: node script.js
+npm start # Alias for: node cli.js
+```
+
+## Architecture
+
+### Core Files
+- **cli.js** - Entry point that imports and runs the script using `@octoherd/cli/run`
+- **script.js** - Main script logic exported as `async function script(octokit, repository, options)`
+
+### Workflow Logic (script.js)
+
+The script follows this sequence for each repository:
+
+1. **Safety checks** (lines 46-61):
+   - Skip archived repositories
+   - Check for `octoherd-no-touch` topic to skip protected repos
+
+2. **PR Discovery** (lines 63-100):
+   - Search for PRs matching the expected title pattern
+   - For special cases (`all` and `projen`), check `maxAgeDays` to avoid stale merged PRs
+   - Skip if PR is already merged, closed, or in draft state
+
+3. **PR Validation** (lines 104-191):
+   - Uses GraphQL query to fetch comprehensive PR status
+   - Checks: mergeable state, review decision, CI status (statusCheckRollup)
+   - Exits early if PR cannot be updated, CI failing, or conflicts exist
+
+4. **Auto-approval** (lines 193-239):
+   - Attempts to approve PR if not already approved and viewer can approve
+   - Re-checks approval status after attempting approval
+
+5. **Merge** (lines 241-253):
+   - Squash merges the PR with standardized commit title format
+
+6. **Workflow Re-run** (lines 256-305):
+   - If no PR exists, finds the relevant workflow (renovate.yml or update-projen-main.yml)
+   - Checks if workflow is already running
+   - Validates that at least 30 minutes have passed since the last workflow run (throttling)
+   - Re-runs the last workflow if it's not currently active and throttle period has elapsed
+   - Throttling prevents excessive CI usage when the script runs frequently
+
+### Special Cases
+
+The script handles three distinct patterns via the `--majorVersion` parameter:
+
+- **Standard major version** (e.g., `v11`): Targets PRs like "fix(deps): update dependency @time-loop/cdk-library to v11"
+- **`all`**: Targets "fix(deps): update all non-major dependencies" PRs, uses `maxAgeDays` parameter
+- **`projen`**: Targets "fix(deps): upgrade projen" PRs from `update-projen-main` workflow, uses `maxAgeDays` parameter
+
+### Options
+
+- `--majorVersion` (required): Major version (e.g., `v11`), `all`, or `projen`
+- `--library` (default: `@time-loop/cdk-library`): Library name (ignored for `all` and `projen`)
+- `--maxAgeDays` (default: 7): Maximum age in days for merged PRs (only used with `all` and `projen`)
+- `--merge` (default: true): Whether to merge PRs. Use `--no-merge` to validate PRs without actually merging them
+
+### PAT Requirements
+
+The GitHub Personal Access Token needs:
+- `repo` - Full control of private repositories
+
+## Key Implementation Details
+
+- Uses `@octoherd/cli` framework for multi-repository operations
+- Combines REST API and GraphQL for comprehensive PR status checking
+- Workflow re-run logic ensures Renovate runs are triggered when PRs don't exist
+- The `noTouchTopicName` constant (`octoherd-no-touch`) provides escape hatch for repositories