feat: Implement platform-specific hosts file path retrieval

- Created a new `platform` package to handle OS-specific hosts file paths.
- Added implementations for macOS, Linux, and Windows to retrieve the hosts file path.
- Introduced tests for the `GetHostsFilePath` function to ensure correct behavior across platforms.

feat: Add DNS resolver for IP lookups

- Implemented a `resolver` package for performing DNS lookups.
- Created a `DNSResolver` struct with a `LookupIP` method to handle A-record lookups and CNAME resolution.
- Added comprehensive tests for various DNS scenarios, including CNAME chains and error handling.

chore: Refactor project structure and update dependencies

- Restructured the project to follow Go's standard package layout.
- Updated `go.mod` to Go 1.20 and added `golang.org/x/net` dependency.
- Removed old source files and ensured a clean build with all tests passing.

.gitignore

@@ -1,5 +1,23 @@
 # Build outputs
+build/
 bin/
+*.exe
+*.out
+*.test
+
+# Dependencies
+vendor/
 
 # IDE files
-.idea/
+.idea/
+.vscode/
+
+# OS files
+.DS_Store
+Thumbs.db
+
+# Temp and logs
+*.tmp
+*.swp
+*.log
+.env*