Initial implementation of jrx - JSX factory for json-render

JSX factory that compiles JSX trees into json-render Spec JSON.
Framework-agnostic custom jsx-runtime, no React dependency at runtime.

- jsx/jsxs/Fragment via jsxImportSource: "jrx"
- render() flattens JrxNode tree into { root, elements, state? } Spec
- Auto key generation (type-N) with explicit key override
- Full feature parity: visible, on, repeat, watch as reserved props
- Function components via component() or plain functions
- @json-render/core as peer dependency

Co-authored-by: Ona <no-reply@ona.com>

tsup.config.ts

@@ -0,0 +1,12 @@
+import { defineConfig } from "tsup";
+
+export default defineConfig({
+  entry: ["src/index.ts", "src/jsx-runtime.ts", "src/jsx-dev-runtime.ts"],
+  format: ["cjs", "esm"],
+  dts: true,
+  sourcemap: true,
+  clean: true,
+  jsx: "transform",
+  jsxFactory: "jsx",
+  jsxFragment: "Fragment",
+});