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.

.pre-commit-config.yaml

@@ -1,18 +1,32 @@
 repos:
   - repo: https://github.com/astral-sh/ruff-pre-commit
-    rev: v0.15.13
+    rev: v0.15.20
     hooks:
       - id: ruff-check
-        types_or: [python, pyi]
-        args: [--fix]
+        types_or: [ python, pyi ]
+        args: [ --fix ]
       - id: ruff-format
-        types_or: [python, pyi]
+        types_or: [ python, pyi ]
 
   - repo: local
     hooks:
       - id: ty
         name: ty check
-        entry: uvx ty check
-        language: python
-        types_or: [python, pyi]
+        entry: uv run ty check
+        language: system
+        types_or: [ python, pyi ]
+        pass_filenames: false
+
+      - id: ultracite
+        name: ultracite
+        entry: bash -c 'cd ui && bun x ultracite fix'
+        language: system
+        files: ^ui/
+        pass_filenames: false
+
+      - id: svelte-check
+        name: svelte check
+        entry: bash -c 'cd ui && bun check'
+        language: system
+        files: ^ui/
         pass_filenames: false