/ci

Summarize the latest GitHub Actions runs, surface results, and analyze issues.

# Goal

Pull the most recent GitHub Actions workflow runs for a repo, summarize their status, and analyze failures with actionable diagnostics and next steps.

# Inputs

- `$ARGUMENTS` can be:
  - Optional flags:
    - `workflow=<file|id>|all` (e.g., `workflow=ci.yml` or `workflow=all`; default: all workflows)

# Plan

1. **Resolve repository coordinates**
   - You usually know what the current owner/repo are (often repo is the folder name).
   - If `owner/repo` is unclear, infer from local git:
     - Verify repo: !`git rev-parse --is-inside-work-tree`
     - Remote URL: !`git remote get-u...