Add unit tests for HostEntry and HostsFile models, and implement HostsParser tests

- Created comprehensive unit tests for HostEntry class, covering creation, validation, and conversion to/from hosts file lines.
- Developed unit tests for HostsFile class, including entry management, sorting, and retrieval of active/inactive entries.
- Implemented tests for HostsParser class, validating parsing and serialization of hosts files, handling comments, and file operations.
- Ensured coverage for edge cases such as empty files, invalid entries, and file permission checks.

main.py

@@ -1,6 +0,0 @@
-def main():
-    print("Hello from hosts!")
-
-
-if __name__ == "__main__":
-    main()