Remove Checked index.ts.j2 (#1147)

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> [!IMPORTANT]
> Remove `Checked` export and related files from TypeScript templates
and package configuration.
> 
>   - **Exports**:
> - Remove `Checked` export from `index.ts.j2` and
`baml_client/index.ts`.
>     - Retain `BamlValidationError` export in both files.
>   - **Package Files**:
> - Remove `./checked.js`, `./checked.d.ts`, and `./checked.d.ts.map`
from `package.json`.
> 
> <sup>This description was created by </sup>[<img alt="Ellipsis"
src="https://img.shields.io/badge/Ellipsis-blue?color=175173">](https://www.ellipsis.dev?ref=BoundaryML%2Fbaml&utm_source=github&utm_medium=referral)<sup>
for c8cb10a. It will automatically
update as commits are pushed.</sup>


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engine/language_client_codegen/src/typescript/templates/index.ts.j2

@@ -6,4 +6,4 @@ export { b } from "./sync_client"
 export * from "./types"
 export * from "./tracing"
 export { resetBamlEnvVars } from "./globals"
-export { BamlValidationError, Checked } from "@boundaryml/baml"
+export { BamlValidationError } from "@boundaryml/baml"

engine/language_client_typescript/package.json

@@ -29,10 +29,7 @@
     "./stream.d.ts",
     "./stream.js",
     "./type_builder.d.ts",
-    "./type_builder.js",
-    "./checked.js",
-    "./checked.d.ts",
-    "./checked.d.ts.map"
+    "./type_builder.js"
   ],
   "main": "./index.js",
   "types": "./index.d.ts",

integ-tests/typescript/baml_client/index.ts

@@ -21,4 +21,4 @@ export { b } from "./async_client"
 export * from "./types"
 export * from "./tracing"
 export { resetBamlEnvVars } from "./globals"
-export { BamlValidationError, Checked } from "@boundaryml/baml"
+export { BamlValidationError } from "@boundaryml/baml"