Add api-extractor check to catch missing exports (#541)

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Signed-off-by: Nik Nasr <[email protected]>

Author: nikrooz

.api/.gitkeep

@@ -12,3 +12,5 @@ packages/*/dist/*
 packages/*/src/generated/*
 packages/*/buf.lock
 
+.api/*
+!.api/.gitkeep