* feat: make upload file size limits configurable via .env
Add UPLOAD_MAX_*_MB environment variables for documents, images, videos,
exercise assignment files, AI assistant documents, landing page images,
and media thumbnails. API presign routes validate file size server-side;
dashboard UI reads the same limits from layout data.
* chore: wire upload limit env vars through Docker compose and docs
Pass UPLOAD_MAX_*_MB from the root .env into api and dashboard containers
in both compose files, document them in .env.example and self-hosting guides.
Co-authored-by: Rotimi Best <[email protected]>
* docs: cross-link upload limits in README, Railway, Coolify, and Cloudflare guides
Co-authored-by: Rotimi Best <[email protected]>
* fix: address PR review feedback on upload limits
- Restore 5 MB default for thumbnail uploads (edit-asset-dialog regression)
- Add getResolvedUploadLimits() fallback for Storybook/tests
- Cache core getUploadLimits() like the dashboard helper
- Document presign fileSize as advisory; allow zero-byte fileSize in schema
- Only send fileSize to presign when greater than zero
* docs: remove upload limits from Cloudflare setup guide
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