Initial implementation of mcq — document reading queue

Single-binary service: push raw markdown via REST/gRPC API, read rendered
HTML through mobile-friendly web UI. MCIAS auth on all endpoints, SQLite
storage, goldmark rendering with GFM and syntax highlighting.

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

internal/db/db.go

@@ -0,0 +1,23 @@
+package db
+
+import (
+	"database/sql"
+	"fmt"
+
+	mcdsldb "git.wntrmute.dev/mc/mcdsl/db"
+)
+
+// DB wraps a SQLite database connection.
+type DB struct {
+	*sql.DB
+}
+
+// Open opens (or creates) a SQLite database at the given path with the
+// standard Metacircular pragmas: WAL mode, foreign keys, busy timeout.
+func Open(path string) (*DB, error) {
+	sqlDB, err := mcdsldb.Open(path)
+	if err != nil {
+		return nil, fmt.Errorf("db: %w", err)
+	}
+	return &DB{sqlDB}, nil
+}