Workspace sync and payload chunking

Workspace synchronisation wakes sleeping containers on demand, prunes cache trees, and splits large payloads to prevent transfer stalls.

Synchronising local files into a container used to fail if the container was stopped. The sync endpoint checks the runtime state now and starts the container before scanning files.

Caches, build directories, and cloud storage folders are ignored during discovery. This brought the initial index time down from minutes to under three seconds.

Payload limits

Sending hundreds of files in a single request exceeded the body limit on larger projects. Uploads are streamed in bounded four-megabyte chunks now, and files above five megabytes are skipped with a warning.