docs(generators): add tip for tsx users about importFileExtension (#7714)

Users running Prisma 7's generated client with tsx frequently encounter
'Cannot find module ./internal/class.js' errors because tsx cannot resolve
.js imports to .ts files. This adds a tip explaining the fix
(importFileExtension = "ts") directly in the generators reference.

Addresses recurring questions in Discussions #29318, #29347.

Author: Andrew1326

apps/docs/content/docs/orm/prisma-schema/overview/generators.mdx

@@ -154,6 +154,22 @@ Below are the options for the `prisma-client` generator:
 
 :::
 
+:::tip
+
+**Using `tsx` as your TypeScript runner?** If you see `Cannot find module './internal/class.js'` errors at runtime, set `importFileExtension = "ts"` in your generator block:
+
+```prisma
+generator client {
+  provider            = "prisma-client"
+  output              = "../src/generated/prisma"
+  importFileExtension = "ts"
+}
+```
+
+This happens because the generated client uses `.js` extensions in its import statements (ESM convention), but `tsx` cannot resolve `.js` imports to the corresponding `.ts` files on disk. Setting `importFileExtension = "ts"` ensures the generated imports match what `tsx` expects.
+
+:::
+
 ### Importing types
 
 The new `prisma-client` generator creates individual `.ts` files which allow for a more fine granular import of types. This can improve compile and typecheck performance and be useful for tree-shaking, too.