workflow: GitHub hooks automation for coding agents

[Copilot]

Summary

Adds two GitHub Actions workflows that eliminate manual steps in the coding-agent workflow: label-to-assign and post-merge retrospective reminder.

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Changes

.github/workflows/issue-copilot-assign.yml

• Triggers on issues.labeled (label = copilot)
• Calls addAssignees to assign the issue to @copilot, which auto-creates the copilot/* branch + draft PR and starts the Workflow Orchestrator

.github/workflows/pr-merge-retrospective.yml

• Triggers on pull_request.closed (merged=true, feature/* or fix/* head branch)
• Extracts work item path from branch name, posts a structured comment with retrospective instructions

docs/agents.md

• New GitHub Hooks Automation section documenting both workflows, triggers, and a table of future candidates
• Updated Automated Orchestration entry point: label-first is now the primary trigger path

docs/workflow/117-github-hooks-automation/tasks.md

• Full exploration: inventory of all unused GitHub events, rationale, effort/impact/risk scoring, and three future candidates (PR review → developer notify, CI failure → developer feedback, scheduled agent validation health check)

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Checklist

• All checks pass (build, test, lint)
• Commits follow Conventional Commits
• PR description uses the standard template (Problem / Change / Verification)

Merge method: Use Rebase and merge to maintain a linear history. The repository enforces rebase-only merges by default.

Create & merge guidance: Use scripts/pr-github.sh create to create PRs, and scripts/pr-github.sh create-and-merge to perform the merge (this script is the authoritative, repo-preferred tool for PR creation and merges). If you need to inspect/check the PR, use GitHub chat tools (github/*) as needed.

Original prompt

Explore how we could use github hooks to further improve and automate our development worklflow for coding agents.

Custom agent used: Workflow Engineer (coding agent)
Analyze, improve, and maintain the agent workflow

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📍 Connect Copilot coding agent with Jira, Azure Boards or Linear to delegate work to Copilot in one click without leaving your project management tool.