Add: dns leak detection

docs/WORK_ITEMS_v0.3.0.md

@@ -29,17 +29,17 @@ This is a practical checklist to execute v0.3.0.
 - [x] diff categories: add/remove/expired/changed
 
 ## 6) optional LLMNR/NBNS
-- [ ] implement `discover llmnr`
-- [ ] implement `discover nbns`
-- [ ] bounded collection, low-noise
+- [x] implement `discover llmnr`
+- [x] implement `discover nbns`
+- [x] bounded collection, low-noise
 
 ## 7) docs updates
 - [x] update README roadmap
-- [ ] update COMMANDS.md with new flags/commands
-- [ ] add RELEASE_v0.3.0.md
+- [x] update COMMANDS.md with new flags/commands
+- [x] add RELEASE_v0.3.0.md
 
 ## 8) optional HTTP/3 (last)
 - [x] add `http3` cargo feature + deps
 - [x] implement `--http3` / `--http3-only`
-- [ ] define error classification for QUIC failures
-- [ ] keep feature disabled in default builds until stabilized
+- [x] define error classification for QUIC failures
+- [x] keep feature disabled in default builds until stabilized