Adding typespec base package reference for liftr (#29569)

* Adding typespec package for liftr base

* Adding typespec base package reference for liftr

* Updating package.json

* Updating version with readme

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Co-authored-by: Allen Zhang <[email protected]>

Author: nikhgup

package-lock.json

@@ -9,6 +9,7 @@
     "@azure-tools/typespec-azure-rulesets": "0.44.0",
     "@azure-tools/typespec-client-generator-cli": "0.9.4",
     "@azure-tools/typespec-client-generator-core": "0.44.2",
+    "@azure-tools/typespec-liftr-base": "0.4.0",
     "@azure/avocado": "^0.8.4",
     "@typespec/compiler": "0.58.1",
     "@typespec/http": "0.58.0",