go-avahi: Add initial fuzzing project with 4 comprehensive harnesses

[rishavtarway]

This PR adds the initial fuzzing infrastructure for the go-avahi project.

Changes:

• Added projects/go-avahi/fuzzer/fuzz_domain.go: Harness to fuzz the DomainNormalize function targeting CGo boundary safety.
• Added projects/go-avahi/fuzzer/fuzz_domain_roundtrip.go: Verifies round-trip consistency between DomainFrom and DomainSlice and identifies logic errors in unescaping.
• Added projects/go-avahi/fuzzer/fuzz_service_name.go: Tests split/join consistency for mDNS service names ensuring stable parsing.
• Added projects/go-avahi/fuzzer/fuzz_state_strings.go: Verifies stability of String methods for library states against arbitrary integer inputs.
• Added projects/go-avahi/oss_fuzz_build.sh: Build script enabling CGo compilation and linking against required system libraries.
• Added integrated seed corpora: Covering edge cases such as Unicode labels, escaped characters, and boundary values.

Testing:

• Verified locally using OSS-Fuzz Docker images and the helper.py framework.
• Validated build success with compile_native_go_fuzzer.
• Confirmed high execution stability and compatibility with AddressSanitizer (ASAN).