chore: remove unused files and code

- Delete obsolete RPM maintainer scripts (postinst, prerm, postrm)
  Scripts are now embedded in ja4sentinel.spec
- Delete unused RPM test script (test-rpm.sh)
  Referenced non-existent el7 builds, not integrated in CI
- Remove unused constants and functions from api/types.go:
  - DefaultInterface, DefaultPort, DefaultBPFFilter
  - DefaultFlowTimeout, DefaultPacketBuffer
  - LogLevelDebug, LogLevelInfo, LogLevelWarn, LogLevelError
  - DefaultConfig() function
- Update Makefile with RPM_DIR variable for consistency

Co-authored-by: Qwen-Coder <qwen-coder@alibabacloud.com>

Makefile

@@ -17,6 +17,9 @@ BINARY_PATH=./cmd/ja4sentinel
 DIST_DIR=dist
 BUILD_DIR=build
 
+# RPM build directory
+RPM_DIR=$(DIST_DIR)/rpm
+
 # Package version (strip 'v' prefix from git tags)
 # Set to explicit version for release builds, or use git-based version for dev builds
 PKG_VERSION ?= 1.0.0
@@ -97,23 +100,23 @@ package: package-rpm
 
 ## package-rpm: Build RPM packages for Rocky Linux 8/9/10, AlmaLinux (requires Docker)
 package-rpm:
-	mkdir -p build/rpm/el8 build/rpm/el9 build/rpm/el10
+	mkdir -p $(RPM_DIR)/el8 $(RPM_DIR)/el9 $(RPM_DIR)/el10
 	@echo "Building RPM packages for Rocky Linux 8/9, AlmaLinux 10..."
 	docker build --target output -t ja4sentinel-rpm-packager:latest \
 		--build-arg VERSION=$(PKG_VERSION) \
 		-f Dockerfile.package .
 	@echo "Extracting RPM packages from Docker image..."
-	@docker run --rm -v $(PWD)/build:/output ja4sentinel-rpm-packager:latest sh -c \
+	@docker run --rm -v $(PWD)/$(RPM_DIR):/output/rpm ja4sentinel-rpm-packager:latest sh -c \
 		'cp -r /packages/rpm/el8 /output/rpm/ && \
 		 cp -r /packages/rpm/el9 /output/rpm/ && \
 		 cp -r /packages/rpm/el10 /output/rpm/'
 	@echo "RPM packages created:"
 	@echo "  Rocky Linux 8 (el8):"
-	ls -la build/rpm/el8/ 2>/dev/null || echo "    (no packages)"
+	ls -la $(RPM_DIR)/el8/ 2>/dev/null || echo "    (no packages)"
 	@echo "  Rocky Linux 9 (el9):"
-	ls -la build/rpm/el9/ 2>/dev/null || echo "    (no packages)"
+	ls -la $(RPM_DIR)/el9/ 2>/dev/null || echo "    (no packages)"
 	@echo "  AlmaLinux/Rocky 10 (el10):"
-	ls -la build/rpm/el10/ 2>/dev/null || echo "    (no packages)"
+	ls -la $(RPM_DIR)/el10/ 2>/dev/null || echo "    (no packages)"
 
 ## test-package-rpm: Test RPM package installation in Docker
 test-package-rpm: package-rpm