feat(ui): forge icons on repo cards (github, gitea, mozilla)

Add SVG icons for each forge before the repo name on dashboard cards.
Icons sourced from user-provided SVGs in ui/public/.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

ui/public/gitea.svg

@@ -0,0 +1,20 @@
+<?xml version="1.0" encoding="utf-8"?>
+
+<!-- Uploaded to: SVG Repo, www.svgrepo.com, Generator: SVG Repo Mixer Tools -->
+<svg xmlns="http://www.w3.org/2000/svg"
+aria-label="Gitea" role="img"
+viewBox="0 0 512 512">
+
+<rect
+rx="15%" height="512" width="512"
+fill="#ffffff"/>
+
+<path d="M419 150c-98 7-186 2-276-1-27 0-63 19-61 67 3 75 71 82 99 83 3 14 35 62 59 65h104c63-5 109-213 75-214zm-311 67c-3-21 7-42 42-42 3 39 10 61 22 96-32-5-59-15-64-54z" fill="#592"/>
+
+<path d="m293 152v70" stroke="#ffffff" stroke-width="9"/>
+
+<g transform="rotate(25.7 496 -423)" stroke-width="7" fill="#592">
+
+<path d="M561 246h97" stroke="#592" />
+
+<rect x="561" y="246" width="97" height="97" rx="16" fill="#ffffff"/>