Add file type validation for import

[swissspidy]

Fixes #597

[github-actions]

Size Change: +212 B (0%)

Total Size: 7.31 MB

Filename	Size	Change
build/media-experiments.js	77.5 kB	+183 B (+0.24%)

ℹ️ View Unchanged

Filename	Size	Change
build/100.js	88.7 kB	0 B
build/699.js	2.35 MB	0 B
build/ai.worker.js	177 kB	0 B
build/blurhash.worker.js	3.23 kB	0 B
build/canvas.worker.js	2.79 kB	0 B
build/chunk-ffmpeg.js	5.92 kB	0 B
build/chunk-selfie-segmentation.js	16.3 kB	0 B
build/dominant-color.worker.js	4.45 kB	0 B
build/ffmpeg.js	1.09 kB	0 B
build/heif.worker.js	450 kB	0 B
build/media-experiments-blocks-rtl.css	297 B	0 B
build/media-experiments-blocks.css	296 B	0 B
build/media-experiments-rtl.css	1.04 kB	0 B
build/media-experiments.css	1.04 kB	0 B
build/pdf.js	579 B	0 B
build/subtitles.js	850 B	0 B
build/view-upload-request-view-rtl.css	716 B	0 B
build/view-upload-request-view.css	717 B	0 B
build/view-upload-request.js	18.5 kB	+29 B (+0.16%)
build/vips-heif.********.wasm	1.27 MB	0 B
build/vips-jxl.********.wasm	800 kB	0 B
build/vips.********.wasm	2 MB	0 B
build/vips.worker.js	37.9 kB	0 B

_{compressed-size-action}