Vite v8 upgrade breaks Lychee

[cdzombak]

Lychee version

b5f994a

Did you check the latest Lychee version?

Yes, I did

Which PHP version are you using?

PHP 8.5

Detailed description of the problem

PR #4221 upgrades Vite to v8. After this change, Lychee fails to load with the following JavaScript error in the console:

Uncaught ReferenceError: L is not defined
    at leaflet-rotatedmarker-2yAeb448.js:1:19
    at leaflet-rotatedmarker-2yAeb448.js:1:1038

Steps to reproduce the issue

1. Deploy Lychee as of commit b5f994a
2. Attempt to load Lychee in the browser

Diagnostics [REQUIRED]

No response

Browser & System [REQUIRED]

Tested in both Safari & Chrome, macOS 15.7.1.

Please confirm (incomplete submissions will not be addressed)

• I have provided easy and step-by-step instructions to reproduce the bug.
• I understand my bug report will be removed if I haven't met the criteria above.
• I understand that if I am requested to provide more information, I must do so within 14 days or the bug report will be closed.

[cdzombak]

Claude Code says,

Vite 8 uses Rolldown instead of Rollup under the hood, which changes how manualChunks isolates modules. In Vite 7/Rollup, the leaflet plugins likely ended up sharing the same module scope as leaflet despite being in separate chunks. In Vite 8/Rolldown, the chunk isolation is stricter — each chunk is a true IIFE/module boundary — so L is no longer a visible global when
leaflet-rotatedmarker runs in its own chunk.

JavaScript build system errors are beyond my knowledge/confidence level to fix, unfortunately.

[ildyria]

Fix incoming:

• Fix vite 8 building a broken frontend #4242
• Leaflet build using Vite 8 rolldown Leaflet/Leaflet#10160