fix: htaccess RewriteBase rules block API requests for files with common extensions

[DeepDiver1975]

Summary

• Fixes jpg files cannot be marked as favorites #41418: files with extensions like .jpg, .png, .svg, .json etc. could not be marked as favorites when htaccess.RewriteBase is configured
• Replaces the URI extension-based RewriteCond with RewriteCond %{REQUEST_FILENAME} \!-f, which correctly routes virtual API paths through index.php while still letting Apache serve real static assets directly
• Adds a regression test verifying the generated .htaccess content uses the file-existence check and not the extension pattern

Root cause

updateHtaccess() in lib/private/Setup.php generated this condition when htaccess.RewriteBase was set:

RewriteCond %{REQUEST_URI} \!\.(css|js|svg|gif|png|html|ttf|woff|ico|jpg|jpeg|json|properties)$
RewriteCond %{REQUEST_URI} \!\.(min|js|auto)\.map$

The intent was to bypass PHP for static asset requests, but it matched on the URI string alone. So POST /apps/files/api/v1/files/photo.jpg — a valid API call — matched the .jpg exclusion and was never routed to index.php, causing a 405 Method Not Allowed response.

Fix

RewriteCond %{REQUEST_FILENAME} \!-f

%{REQUEST_FILENAME} resolves to the filesystem path. \!-f means "if no actual file exists at this path" — so real static files are served directly, and virtual API paths route through PHP.

Test plan

• Mark a .jpg file as a favorite — should succeed (previously 405)
• Mark a .png, .svg, .json file as favorite — same
• Static assets (CSS, JS, images) still load correctly
• Run tests/lib/SetupTest.php — new test testUpdateHtaccessWithRewriteBaseUsesFileExistenceCheck should pass
• Requires htaccess.RewriteBase to be set in config.php to reproduce

🤖 Generated with Claude Code

[phil-davis]

I wonder why we needed to getConfig here previously (and now pass it in)?

There is already a $config in this class that is initialised by anything that creates an instance of this class.

Anyway, I suppose that is history, and maybe the settings in $this->config get stale?

[DeepDiver1975]

this is all history ..... within this change I wanted to make the function testable but not fully refactor it all .... really not worth it ....