feat(ui,infra): SvelteKit ui scaffold, Makefile, pre-commit, claude hooks

ui/: SvelteKit 2 + Svelte 5 + Tailwind 4 + shadcn-svelte (luma, lucide)
on bun with ultracite; adapter-static with SPA fallback; theme tokens
taken from msos. Dockerfile gains a bun stage that builds ui/build.
Makefile and pre-commit cover ruff, ty, ultracite and svelte-check;
.claude settings run the matching fixer after edits. docs/PRODUCT.md
captures product truth for the UI work.

ui/components.json

@@ -0,0 +1,20 @@
+{
+  "$schema": "https://shadcn-svelte.com/schema.json",
+  "tailwind": {
+    "css": "src/routes/layout.css",
+    "baseColor": "neutral"
+  },
+  "aliases": {
+    "components": "$lib/components",
+    "utils": "$lib/utils",
+    "ui": "$lib/components/ui",
+    "hooks": "$lib/hooks",
+    "lib": "$lib"
+  },
+  "typescript": true,
+  "registry": "https://shadcn-svelte.com/registry",
+  "style": "luma",
+  "iconLibrary": "lucide",
+  "menuColor": "default-translucent",
+  "menuAccent": "subtle"
+}