Introduces comprehensive database schema for merge request ingestion
(CP2), designed with forward compatibility for future features.
New tables:
- merge_requests: Core MR metadata with draft status, branch info,
detailed_merge_status (modern API field), and sync health telemetry
columns for debuggability
- mr_labels: Junction table linking MRs to shared labels table
- mr_assignees: MR assignee usernames (same pattern as issues)
- mr_reviewers: MR-specific reviewer tracking (not applicable to issues)
Additional indexes:
- discussions: Add merge_request_id and resolved status indexes
- notes: Add composite indexes for DiffNote file/line queries
DiffNote position enhancements:
- position_type: 'text' | 'image' | 'file' for diff comment semantics
- position_line_range_start/end: Multi-line comment range support
- position_base_sha/start_sha/head_sha: Commit context for diff notes
The schema captures CP3-ready fields (head_sha, references_short/full,
SHA triplet) at zero additional API cost, preparing for file-context
and cross-project reference features.
Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>
