fix(frontend): restore Android-compatible remote asset

[hotzenplotz5]

Summary

• replace the nested JPEG-in-SVG remote asset with a fully self-contained SVG rendering
• preserve the current 360x1220 geometry, 35 functional hotspots, narrow mobile width and vertical scrolling
• retain layered shell gradients, highlights, texture, key bevels and raised shadows without external or embedded raster subresources
• add a frontend contract guard that rejects <image>, data:image/* and feDropShadow in the remote asset

Root cause

PR #110 wrapped a JPEG data URI inside an SVG <image> element. Microsoft Edge on Android loaded the outer SVG but rejected the nested raster image, producing a large broken-image placeholder in the remote dialog.

Validation

• SVG parsed successfully as XML
• SVG rendered successfully to a 540x1830 PNG with Inkscape
• stored branch content verified through GitHub
• existing remote runtime test now checks that the asset is self-contained

Mobile acceptance

Install this branch with make install-runtime, restart the daemon and verify the remote in Microsoft Edge on Android. Keep this PR Draft until that real-device check passes.

[hotzenplotz5]

Closing as stale/superseded. This PR changes an old photorealistic remote asset path that is no longer present in current main. Any Android remote rendering issue should be reproduced and fixed against the current remote implementation rather than merging this historical branch.