Remove the MinIO/S3 storage backend entirely. The filesystem backend is
fully implemented, already used in production, and a migrate-storage tool
exists for any remaining MinIO deployments to migrate beforehand.
Changes:
- Delete MinIO client implementation (internal/storage/storage.go)
- Delete migrate-storage tool (cmd/migrate-storage, scripts/migrate-storage.sh)
- Remove MinIO service, volumes, and env vars from all Docker Compose files
- Simplify StorageConfig: remove Endpoint, AccessKey, SecretKey, Bucket,
UseSSL, Region fields; add SILO_STORAGE_ROOT_DIR env override
- Change all SQL COALESCE defaults from 'minio' to 'filesystem'
- Add migration 020 to update column defaults to 'filesystem'
- Remove minio-go/v7 dependency (go mod tidy)
- Update all config examples, setup scripts, docs, and tests
- SPECIFICATION.md: add 8 KC endpoints to Section 11.1, new Section 11.3
documenting .kc format, extraction pipeline, packing, lifecycle state
machine, and all response shapes. Update endpoint count 78 → 86.
- ROADMAP.md: mark .kc Format Spec as Complete in Tier 0 table
- STATUS.md: add KC features to core systems table, update migration
list through 018, update endpoint count
- MODULES.md: add metadata, dependencies, and macros endpoints to
core module listing
