feat: initial Honcho UI scaffold

React 19 + Vite 8 + TanStack Router SPA for browsing and chatting with
a self-hosted Honcho instance. Configurable base URL stored in localStorage
only. Dark/light theme, framer-motion animations, lucide-react icons.

biome.json

@@ -0,0 +1,31 @@
+{
+  "$schema": "https://biomejs.dev/schemas/1.9.4/schema.json",
+  "vcs": {
+    "enabled": true,
+    "clientKind": "git",
+    "useIgnoreFile": true
+  },
+  "organizeImports": {
+    "enabled": true
+  },
+  "linter": {
+    "enabled": true,
+    "rules": {
+      "recommended": true,
+      "style": {
+        "noNonNullAssertion": "warn"
+      }
+    }
+  },
+  "formatter": {
+    "enabled": true,
+    "indentStyle": "tab",
+    "lineWidth": 100
+  },
+  "javascript": {
+    "formatter": {
+      "quoteStyle": "double",
+      "semicolons": "always"
+    }
+  }
+}