operationNameFromPath
Generates a PascalCase operation name from HTTP method and path. Path parameters like {id} become "ById", {userId} becomes "ByUserId". Handles hyphens, underscores, and dots in path segments.
Examples:
("POST", "/pets") -> "PostPets"
("GET", "/pets/{id}") -> "GetPetsById"
("PUT", "/users/{userId}/orders/{orderId}") -> "PutUsersByUserIdOrdersByOrderId"
("GET", "/api-tokens") -> "GetApiTokens"