refactor(api): restructured API for type safety, maintainability and docs generation

- These changes makes the API incombatible with previous versions
- Added new types for error handling, success responses, and health checks.
- Updated health check logic to utilize the new types for better clarity and structure.
- Refactored existing handlers to improve response consistency and error handling.
- Updated Makefile to include a new target for generating API types from Swagger.
- Updated "new agent" API to respond an encrypted cert pair

Makefile

@@ -134,4 +134,13 @@ cloc:
 	cloc --include-lang=Go --not-match-f '_test.go$$' .
 
 push-github:
-	git push origin $(shell git rev-parse --abbrev-ref HEAD)
+	git push origin $(shell git rev-parse --abbrev-ref HEAD)
+
+gen-swagger:
+	swag init --parseDependency --parseInternal -g handler.go -d internal/api -o internal/api/v1/docs
+	python3 scripts/fix-swagger-json.py
+
+gen-api-types: gen-swagger
+	# --disable-throw-on-error
+	pnpx swagger-typescript-api generate --sort-types --generate-union-enums --axios --add-readonly --route-types \
+		 --responses -o ../godoxy-frontend/src/lib -n api.ts -p internal/api/v1/docs/swagger.json