Add: H3 support - incomplete

docs/RELEASE_v0.3.0.md

@@ -10,7 +10,7 @@ v0.3.0 focuses on improving diagnostic depth and fidelity of existing commands r
 Major upgrades in this release:
 - richer traceroute output and per-hop statistics
 - HTTP timing breakdown accuracy (connect/tls stages)
-- optional HTTP/3 support (best-effort)
+- optional HTTP/3 support (feature-gated; experimental)
 - TLS diagnostics upgrades (OCSP stapling indicator, richer certificate parsing)
 - ports connections view and summaries
 - improved cert baseline/diff for system roots
@@ -67,7 +67,7 @@ Acceptance:
 - on timeout / failure, partial timing must still be meaningful.
 
 ### 3.3 HTTP/3 (optional feature flag) (SHOULD)
-Current: HTTP/3 not implemented.
+Current: feature-gated HTTP/3 path exists but is incomplete; keep disabled in default builds.
 Target:
 - add `--http3` support behind Cargo feature `http3`
 - behavior:
@@ -79,6 +79,7 @@ Target:
 Acceptance:
 - builds without `http3` feature still work
 - with feature enabled, HTTP/3 works on at least one known compatible endpoint
+- documented as experimental until stabilized
 
 ### 3.4 TLS extras: OCSP + richer cert parsing (MUST)
 Current: `tls handshake/verify/cert/alpn` exists.