Function openEmbedReceiptReader

openEmbedReceiptReader(
file: string,
expectedVaultRoot: string,
): Promise<EmbedReceiptReader>
Open an existing embedding database strictly read-only for final receipt validation. This function never bootstraps, rebuilds, migrates, or writes the configured SQLite family: missing files and legacy/incompatible authority schemas are rejected. It does hold private shared coordination markers for the reader lifetime. The main/WAL/SHM/rollback-journal family is checked before dependency loading and again immediately before native open; every present leaf must be a singly linked regular file and the main must exist.
Parameters
- file: string
  Absolute path to an existing .embed.db file.
- expectedVaultRoot: string
  Exact vault root the database must declare.
Returns Promise<EmbedReceiptReader>
A synchronous receipt validator backed by a read-only SQLite handle.
Throws
If file is outside the exact .embed.db namespace; this is checked before dependency loading or filesystem I/O.

Throws
If the file is absent, belongs to another vault, or lacks the current revision ledger contract.
Example
```
const reader = await openEmbedReceiptReader(file, vault.root);
try {
  if (!reader.isCurrentSourceReceipt(path, kind, mtimeMs, revision)) return [];
} finally {
  reader.close();
}
```
- Defined in src/embed-db.ts:3546