AI-powered PR review via Woodpecker pipeline

[jerrod-storm]

Problem

Codeberg has no built-in AI code review integration (unlike GitHub Copilot). PRs currently only get human review.

Proposal

Add an AI-powered PR review step to the shared Woodpecker pipeline.

Preferred: Cursor Cloud Agents + Forgejo MCP

• Deploy goern/forgejo-mcp to give the agent Forgejo API access (read diffs, post comments, check labels)
• Trigger a Cursor Cloud Agent from the Woodpecker pipeline via Cursor's API
• Uses Composer 1.5 (Cursor's in-house model, $3.50/M input tokens, included in Auto on Pro plan)
• Agent-agnostic: MCP server is the stable interface, agent can be swapped later
• Investigate whether Cloud Agents can run against existing Pro subscription credits or require separate "usage-based pricing enablement"

Alternative A: Claude Code CLI + Forgejo MCP

• Same MCP setup, but invoke Claude Code CLI instead of Cursor
• Requires separate Anthropic API key and billing

Alternative B: Direct Claude API (lightest weight)

• Pipeline step fetches PR diff via Forgejo API
• Sends diff to Claude API with review guidelines as system prompt
• Posts response as PR comment via Forgejo API using the Blizz bot account
• ~250 lines of script, no MCP server to maintain
• Requires separate Anthropic API key and billing

Prerequisites

• Forgejo MCP server deployed (for preferred approach and Alt A)
• API key for chosen provider (stored as Woodpecker secret)
• Blizz bot token for posting review comments (already available)
• Review guidelines/system prompt (could be repo-specific via .woodpecker/review-prompt.md or similar)

Notes

• Cursor has no headless IDE mode, but Cloud Agents and Headless CLI (cursor -p --force) work without the IDE
• Should be a shared pipeline step reusable across Shellshock, Violet, and Kaitos