Send content types with static uploads

[batuhan]

Summary

• include each exported file media type in the Spacefast manifest
• send a Content-Type header when upload instructions do not provide one
• use application/octet-stream for unknown extensions
• release as 0.5.5

Verification

• ./bin/test.sh
• ./bin/test-wordpress.sh
• live managed upload accepted the previously rejected PNG when sent as image/png

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[chatgpt-codex-connector]

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[chatgpt-codex-connector]

Avoid capability-filtered MIME lookup for exported assets

When automatic publishing runs through WP-Cron or Simply Static's background queue, there is no authenticated user, so wp_check_filetype() defaults to get_allowed_mime_types(), which excludes HTML and JavaScript for users without unfiltered_html and may be further restricted by upload_mimes. Normal index.html and .js files will therefore be declared and uploaded as application/octet-stream, potentially making pages download and causing browsers to reject scripts. Use an unfiltered MIME map such as wp_get_mime_types() or another lookup independent of upload permissions.

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