Fix LeBlanc Reflection Deathknell via updated rules

[abueide]

Summary

Integrates the reported LeBlanc Reflection / Honest Broker Deathknell fix and bumps Kai to 0.21.2.

• Pins Agni 6fad1183 consistently across existing Git dependencies.
• Two Brokers dying in combat now produce two Gold tokens.
• Temporary killing the Reflection also triggers its copied Deathknell, before Hold scoring.
• Copied triggered/activated abilities retain their script after the token disappears; copied statics update immediately.
• No renderer workaround, unrelated dependency upgrades, or framework wire change.

Depends on abysl/agni#1 — merge that PR first. It contains the red-before/green-after reproduction, ten serialized copy regressions, official rule citations, and independent review follow-up.

Verification

• bash ci/check.sh: passed (10 tests, connectivity driver paths, all-target headless compile against the final pin; Nix supplied Python/native libraries).
• nix-shell ci/format.nix --run 'treefmt --ci': passed.
• Upstream rules: 4,573 unit tests, 13 blob-compatibility tests, 10 match-state tests, and 10 plugin tests passed; fast checks, portable build, and hardening passed.
• Upstream broad replay check has an unrelated baseline Temporal Portal/Repeat payment fixture failure, documented and reproduced with the old plugin in the rules PR.
• Manual GUI/network matches, the full Kai application test suite, and Android builds were not run.

Release notes

Rebuild/harden bundled modules from the Agni revision in Cargo.lock using the existing helpers. Plugin 0.9.1 uses blob v16 and accepts prior supported versions; existing matches remain pinned to their original module. No deployment or package publishing is part of this PR. If Agni is squash-merged, repin this PR to its final main commit before merging.