fix: Generate tsconfig.json for tmp example typecheck

The test-other-example-generation target generates into examples/tmp/
(gitignored) but expected a tsconfig.json that was never created.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

Author: ryukzak

.gitignore

@@ -42,3 +42,4 @@ test-output
 /generated
 .typeschema-cache
 *.cpuprofile
+examples/tmp/

Makefile

@@ -59,6 +59,7 @@ test-all-example-generation: test-other-example-generation
 
 test-other-example-generation:
 	bun run examples/nodge-r4.ts
+	echo '{ "extends": "../../tsconfig.json", "include": ["."] }' > examples/tmp/tsconfig.json
 	$(TYPECHECK) --project examples/tmp/tsconfig.json
 
 test-typescript-r4-example: typecheck format lint