fix: mime validation for multipart

[ferhatelmas]

What kind of change does this PR introduce?

Bug fix

What is the current behavior?

Multipart form-data upload path doesn't bubble errors correctly.
For example, there is a mime error thrown, it will be caught and converted to size error.

What is the new behavior?

Bubble the error if storage error immediately otherwise fallback.

[Copilot]

Pull request overview

Fixes multipart/form-data upload error handling so that storage-layer validation errors (notably invalid/unsupported MIME types) are not incorrectly wrapped as “No content provided”, aligning multipart behavior with the binary upload path.

Changes:

• In fileUploadFromRequest, rethrow StorageBackendError from the multipart parsing/validation block instead of wrapping it in ERRORS.NoContentProvided.
• Add an integration test case to cover disallowed MIME type handling specifically when contentType is provided via multipart form fields.
• Clarify the existing MIME validation test name to indicate it exercises the “binary path”.

Reviewed changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated no comments.

File	Description
src/storage/uploader.ts	Ensures multipart parsing/validation bubbles StorageBackendError (e.g., invalid MIME type) rather than masking it.
src/test/object.test.ts	Adds coverage for multipart contentType field MIME validation and renames the existing “binary path” test for clarity.

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[coveralls]

Coverage Report for CI Build 24181940260

Coverage increased (+0.007%) to 80.826%

Details

• Coverage increased (+0.007%) from the base build.
• Patch coverage: 3 of 3 lines across 1 file are fully covered (100%).
• No coverage regressions found.

Uncovered Changes

No uncovered changes found.

Coverage Regressions

No coverage regressions found.

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Coverage Stats

Relevant Lines:	37223
Covered Lines:	30265
Line Coverage:	81.31%
Relevant Branches:	4136
Covered Branches:	3164
Branch Coverage:	76.5%
Branches in Coverage %:	Yes
Coverage Strength:	317.55 hits per line

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💛 - Coveralls