Code Review

This pull request introduces synchronous OPFS access mode support in OPFSStore and ArtifactOPFSCache for dedicated worker contexts, allowing for faster read and write operations. The feedback identifies a critical memory regression in async mode where files are loaded entirely into memory as ArrayBuffers instead of using lazy Blobs, which could cause OOM crashes. Additionally, the reviewer suggests adding a try-catch fallback for concurrent createSyncAccessHandle calls to prevent lock failures, and wrapping ArrayBuffers in Uint8Arrays to maintain compatibility with older browser implementations of the OPFS API.

Code Review

This pull request introduces synchronous OPFS (Origin Private File System) access capabilities to OPFSStore and ArtifactOPFSCache via a new OPFSAccessMode option, allowing for synchronous reads and writes in supported dedicated worker contexts. It also adds support for reading cached data directly as an ArrayBuffer. The review feedback highlights two robustness issues in OPFSStore: first, a potential cache corruption scenario where a failed payload overwrite leaves an outdated metadata file intact, which can be mitigated by deleting the metadata file before writing the payload; second, a potential crash during cache reads if the metadata file is corrupted, which should be handled gracefully with a try-catch block to treat it as a cache miss.

Code Review

This pull request introduces synchronous access mode support (OPFSAccessMode) to the Origin Private File System (OPFS) artifact cache, allowing the use of synchronous access handles in dedicated worker contexts for improved performance. The review feedback highlights several critical improvement opportunities in opfs_store.ts. Specifically, the reviewer recommends aborting writable streams on error in writePayloadWithWritable and writeRecord to prevent persistent file locks, using a sync access handle's getSize() in hasExpectedPayloadSize to avoid the overhead of creating large Blob objects, and returning a lazy Blob instead of an eager ArrayBuffer in read to mitigate memory pressure.

LGTM, thanks @akaashrp!