Initial commit: project setup and db package

- Project scaffolding: go.mod, Makefile, .golangci.yaml, doc.go
- README, ARCHITECTURE, PROJECT_PLAN, PROGRESS documentation
- db package: Open (WAL, FK, busy timeout, 0600 permissions),
  Migrate (sequential, transactional, idempotent),
  SchemaVersion, Snapshot (VACUUM INTO)
- 11 tests covering open, migrate, and snapshot

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

PROGRESS.md

@@ -0,0 +1,34 @@
+# MCDSL Progress
+
+## Current State
+
+Phase 1 complete. The `db` package is implemented and tested.
+
+## Completed
+
+### Phase 0: Project Setup (2026-03-25)
+- Initialized Go module (`git.wntrmute.dev/kyle/mcdsl`)
+- Created `.golangci.yaml` matching platform standard (with `exported` rule
+  enabled since this is a shared library)
+- Created `Makefile` with standard targets (build, test, vet, lint, all)
+- Created `.gitignore`
+- Created `doc.go` package doc
+- `make all` passes clean
+
+### Phase 1: `db` — SQLite Foundation (2026-03-25)
+- `Open(path string) (*sql.DB, error)` — opens with WAL, FK, busy timeout
+  5000ms, 0600 permissions, creates parent dirs
+- `Migration` type with Version, Name, SQL fields
+- `Migrate(database *sql.DB, migrations []Migration) error` — sequential,
+  transactional, idempotent, records name and timestamp in schema_migrations
+- `SchemaVersion(database *sql.DB) (int, error)` — highest applied version
+- `Snapshot(database *sql.DB, destPath string) error` — VACUUM INTO with
+  0600 permissions, creates parent dirs
+- 11 tests: open (pragmas, permissions, parent dir, existing DB), migrate
+  (fresh, idempotent, incremental, records name), schema version (empty),
+  snapshot (data integrity, permissions, parent dir)
+- `make all` passes clean (vet, lint 0 issues, 11/11 tests, build)
+
+## Next Steps
+
+- Phase 2: `auth` package (MCIAS token validation with caching)