docs: add OpenAPI-first wiki (overview, components, use cases for templates/client/codegen, design, security, error handling, testing) and refresh lib docs index

openapi_first/templates/vet_app/__init__.py

@@ -50,11 +50,11 @@ Scaffolding via CLI
 
 Create a new vet clinic service using the bundled template:
 
-    openapi-first vet_app
+    openapi-first scaffold vet_app
 
 Create the service in a custom directory:
 
-    openapi-first vet_app my-vet-clinic
+    openapi-first scaffold vet_app my-vet-clinic
 
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 Client Usage Example