Fix single file download to an output path without a directory

[harminius]

mergin download-file crashed with FileNotFoundError: '' when the output was a bare filename (db.gpkg or ./db.gpkg), because os.path.dirname returns an empty string and os.makedirs("") fails. This became easy to hit with the new --project option, where writing to the current directory is the natural usage.

The output directory is now resolved with os.path.abspath.

The same fix is applied in get_file_diff and create_report, which had the identical pattern.

Seems safe as abspath(p) is normpath(join(os.getcwd(), p)).

related #318

[coveralls]

Coverage Report for CI Build 37923680629

Coverage increased (+0.03%) to 84.013%

Details

• Coverage increased (+0.03%) from the base build.
• Patch coverage: 17 of 17 lines across 4 files 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:	5980
Covered Lines:	5024
Line Coverage:	84.01%
Coverage Strength:	0.84 hits per line

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💛 - Coveralls

[MarcelGeo]

Ok