The legacy pkg/persistence/migrations (DBMigration / dbmXXX) system now
coexists with Alembic but accepts no new migrations — all new schema
changes go through Alembic.
- remove dbm026_llm_model_context_length (superseded by Alembic
0005_add_llm_context_length, which makes the identical change)
- cap required_database_version at 25 (legacy chain dbm001-025 kept
read-only to upgrade pre-existing 3.x DBs to the Alembic baseline)
- add migrations/README.md documenting the freeze
- document the Alembic-only policy and revision-id/idempotency rules in
AGENTS.md
Add the codegraph stdio MCP server to .mcp.json and the CodeGraph usage
guidance block to AGENTS.md, so coding agents working in this repo can use the
codegraph_* structural-search tools.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
