* Reject snapshot upload without collection config before loading it
The raw IO error from `CollectionConfigInternal::load` embedded the
server-side temporary path in the API response. Check for the file first
and return a fixed bad-input error instead.
Part of #10553
Co-Authored-By: Claude Fable 5.1 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01A3o9eWSZNMa6WAs5F2HMZC
* Fix missing-config check to run before restore_snapshot loads config
The path-leak guard lived after Collection::restore_snapshot, but that
function already calls CollectionConfigInternal::load and surfaced the
temp path as a 500. Require a regular config.json file before loading,
and cover a directory-shaped config entry in the openapi test.
* Use a valid empty TAR in the missing-config snapshot upload test
Avoid depending on malformed-archive handling; exercise the missing
collection-config path with a real TAR that has no entries.
---------
Co-authored-by: Claude Fable 5.1 <noreply@anthropic.com>
Co-authored-by: qdrant-cloud-bot <111755117+qdrant-cloud-bot@users.noreply.github.com>
