A text image fill was always laid over the whole text box, so a pasted
image span showed another part of the picture in a box of another size.
Text image fills now honour the image transform, as shape fills do: the
image covers the transform rect instead of the whole box. Paste gives
each pasted image span a transform that keeps the image at the same
pixel offset from the span, like the gradients.
The SVG export emits one linked image per span transform, rather than
one per image id, and the style panel keeps the transform it reads back.
AI-assisted-by: claude-opus-5-5
Emit clipped `<image href>` for fills with a registered media URL instead
of Skia base64 embeds. Register URLs from the frontend and exporter via
store_image_url. Cover rect, path, frame, and text (glyph clip) cases in
SVG export tests.
Closes#11383
* 🔧 Support background blur on PDF render for strokes and text shapes
* ✨ Add LRU eviction to the wasm image store
* ✨ Add RasterFormat to encode png, jpeg and webp from wasm
* 🐛 Fix client-side wasm export encoding jpeg and webp as png
