feat: initial commit — crema-app-aifirst-template

Hybrid traditional + AI-first webapp scaffold. Sibling to crema-app-template,
adds the AI assistant surface, command bus, scripts dialog, and virtual
cursor.

What's pre-wired:
- 6 routes: Overview, Resources, Activity, Assistant, Library, Settings
- Collapsible rail + appbar + avatar dropdown shell (template code, not a lib)
- Mobile sheet at <md
- /assistant: streaming chat via @crema/llm-ui, mock fallback, model selector,
  token meter, retry probe, stop-while-streaming, persistent UI Control toggle
- /settings: editable LM Studio endpoint + context window + response cap, with
  test-connection button
- Markdown rendering for assistant replies; ```action``` blocks rendered as a
  small "Ran N actions" pill
- ⌘⇧P script runner dialog + Play icon in the appbar
- Two demo scripts in public/scripts/
- mightypix theme as default, scoped via <AppShell theme="mightypix">

Libs wired in tsconfig + app.css:
- @crema/action-bus (the bus, parser, runner, cursor, provider, ws, llm-bridge)
- @crema/llm-ui, @crema/chat-ui, @crema/aifirst-ui, @crema/notification-ui
- lib-theme-mightypix

Docs:
- README.md — pitch + quick start + structure
- docs/AI_FIRST.md — full system tour (data-action contract, bus, DSL, scripts,
  cursor, LLM integration)
- app/components/layout/THEME_CONTRACT.md — every CSS variable a theme must declare
- CLAUDE.md — orientation for an LLM working in the repo

Genericized from comfy-cloud (the original prototype):
- Brand defaults to "App" / Sparkles icon (override via app/lib/identity.ts)
- User defaults to a stub (swap useUser() for real auth)
- localStorage namespace is "crema.*" (was "comfy.*")

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

app/components/ui/checkbox.tsx

@@ -0,0 +1,29 @@
+"use client"
+
+import { Checkbox as CheckboxPrimitive } from "@base-ui/react/checkbox"
+
+import { cn } from "~/lib/utils"
+import { CheckIcon } from "lucide-react"
+
+function Checkbox({ className, ...props }: CheckboxPrimitive.Root.Props) {
+  return (
+    <CheckboxPrimitive.Root
+      data-slot="checkbox"
+      className={cn(
+        "peer relative flex size-4 shrink-0 items-center justify-center rounded-[4px] border border-input transition-colors outline-none group-has-disabled/field:opacity-50 after:absolute after:-inset-x-3 after:-inset-y-2 focus-visible:border-ring focus-visible:ring-3 focus-visible:ring-ring/50 disabled:cursor-not-allowed disabled:opacity-50 aria-invalid:border-destructive aria-invalid:ring-3 aria-invalid:ring-destructive/20 aria-invalid:aria-checked:border-primary dark:bg-input/30 dark:aria-invalid:border-destructive/50 dark:aria-invalid:ring-destructive/40 data-checked:border-primary data-checked:bg-primary data-checked:text-primary-foreground dark:data-checked:bg-primary",
+        className
+      )}
+      {...props}
+    >
+      <CheckboxPrimitive.Indicator
+        data-slot="checkbox-indicator"
+        className="grid place-content-center text-current transition-none [&>svg]:size-3.5"
+      >
+        <CheckIcon
+        />
+      </CheckboxPrimitive.Indicator>
+    </CheckboxPrimitive.Root>
+  )
+}
+
+export { Checkbox }