chore(ui): configure the @reui registry for shadcn installs (#6356)

Registers the authenticated @reui registry, flips rsc to true so shadcn
stops stripping "use client" on the way in, and maps the bare
@multica/ui/components and @multica/ui/lib aliases that every registry
item targeting those roots needs to resolve.

Config only: no vendored blocks, no new dependencies.

Co-authored-by: Lambda <agent@multica.ai>
Co-authored-by: multica-agent <github@multica.ai>

CLAUDE.md

@@ -181,6 +181,8 @@ Root-level reminders:
 ## UI Rules
 
 - Prefer shadcn/Base UI components over custom implementations. Add them with `pnpm ui:add <component>` from the repo root.
+- The Pro `@reui` registry is configured in `packages/ui/components.json`; add items with `pnpm ui:add @reui/<name>` and answer `n` to every overwrite prompt so local component customizations survive. It reads `REUI_LICENSE_KEY` from the environment — agents get it from their Multica agent environment, humans export it in their own shell. Never write the key into a repo file.
+- ReUI ships source, not a dependency: route the vendored output to our layout (new primitives to `packages/ui/components/ui/`, compositions to `packages/views/<domain>/`) and rewrite it to our conventions before committing.
 - Use design tokens and semantic classes; avoid hardcoded colors.
 - Do not introduce extra local state unless the design requires it.
 - Handle overflow, long text, scrolling, alignment, and spacing deliberately.

packages/ui/components.json

@@ -1,7 +1,7 @@
 {
   "$schema": "https://ui.shadcn.com/schema.json",
   "style": "base-nova",
-  "rsc": false,
+  "rsc": true,
   "tsx": true,
   "tailwind": {
     "config": "",
@@ -17,5 +17,13 @@
     "hooks": "@multica/ui/hooks",
     "lib": "@multica/ui/lib",
     "utils": "@multica/ui/lib/utils"
+  },
+  "registries": {
+    "@reui": {
+      "url": "https://reui.io/r/base-nova/{name}.json",
+      "headers": {
+        "Authorization": "Bearer ${REUI_LICENSE_KEY}"
+      }
+    }
   }
 }

packages/ui/tsconfig.json

@@ -6,7 +6,9 @@
     "paths": {
       "@/lib/utils": ["./lib/utils.ts"],
       "@/hooks/*": ["./hooks/*"],
-      "@/components/ui/*": ["./components/ui/*"]
+      "@/components/ui/*": ["./components/ui/*"],
+      "@multica/ui/components": ["./components"],
+      "@multica/ui/lib": ["./lib"]
     }
   },
   "include": ["**/*.ts", "**/*.tsx"],