extract tidy-tree layout into separate package

on-behalf-of: @Mermaid-Chart <hello@mermaidchart.com>

packages/mermaid-layout-tidy-tree/tsconfig.json

@@ -0,0 +1,10 @@
+{
+  "extends": "../../tsconfig.json",
+  "compilerOptions": {
+    "rootDir": "./src",
+    "outDir": "./dist",
+    "types": ["vitest/importMeta", "vitest/globals"]
+  },
+  "include": ["./src/**/*.ts"],
+  "typeRoots": ["./src/types"]
+}