feat: add bgpkit-parser v0.19 extended filters, remove unused deps

[digizeph]

Summary

• Added nine bgpkit-parser v0.19 extended element filters to monocle search, monocle parse, and the SSE search API: --otc, --next-hop, --origin, --local-pref, --med, --atomic-aggregate, --aggr-asn, --aggr-ip, --peer-bgp-id. Optional-attribute filters support * (present) and !* (absent) presence wildcards.
• Removed unused radar-rs dependency (Cloudflare Radar API support was removed during the lens refactor but the Cargo.toml entry survived).
• Fixed bgpkit-parser dev-dependency version conflict: [dev-dependencies] pinned v0.18.0 while the main dependency uses v0.19.0, causing E0464: multiple candidates for rlib on cargo test --all-features.

Changes

File	Change
Cargo.toml	Remove radar-rs, remove dev-dep bgpkit-parser = "0.18.0"
src/lens/parse/mod.rs	Add 9 new ParseFilters fields + validate_extended_filters() + 3 unit tests
src/server/search.rs	Add new fields to SearchStreamFilters SSE DTO
src/lens/search/mod.rs	Update test structs to ..Default::default()
src/lens/mod.rs	Fix stale doc comment (radar-rs → ipnet, bgpkit-commons)
CHANGELOG.md	Document all changes

Test plan

• cargo build — clean
• cargo clippy --all-features -- -D warnings — clean
• cargo fmt --check — clean
• cargo test --lib — 296 passed, 0 failed
• cargo test --lib (filter tests) — 5/5 passed, including 3 new tests for extended filter validation and parser wiring
• All 9 new CLI flags present in both monocle search --help and monocle parse --help
• radar-rs absent from cargo tree
• Single bgpkit-parser entry in Cargo.lock