[ISSUE #10384] Enforce Lite exclusive subscription eviction via server-side tombstones

[f1amingo]

Which Issue(s) This PR Fixes

• Fixes [Enhancement] Server-side enforcement for Lite exclusive subscription eviction #10384

Brief Description

Lite exclusive eviction relied on a fire-and-forget unsubscribe notification. When the client missed it, the old consumer kept pulling, causing double consumption and breaking the exclusive contract.This PR adds a broker-local, in-memory tombstone keyed by (clientId, lmqName) as a server-side fallback:

• Written synchronously on eviction, before client notification.
• Checked at the Lite pull entry; rejected pulls reuse the existing "no message available" semantics, requiring no client change.
• Lifecycle-aligned with the client's subscription set — cleared on explicit resubscription, full-sync reconciliation, and disconnect/timeout.
• Self-heals lost notifications by re-sending unsubscribe when a heartbeat still reports a tombstoned lmqName.

How Did You Test This Change?

• New unit tests for ExclusiveEvictionTombstones: add / contains / remove / removeAllOf / retainOnly with prefix-isolation and concurrency cases.
• Extended LiteSubscriptionRegistryImplTest to cover:
  • Tombstone written on exclusive eviction;
  • Self-clear on the evicted client's resubscription;
  • Full-sync reconciliation: stale GC via retainOnly and re-notify on intersection;
  • Cleanup on disconnect/timeout, including the thisSub == null short-circuit path.
• Updated PopLiteMessageProcessorTest for the clientId-aware pull path: pulls from a tombstoned client are rejected and return the "no message" result.
• All affected modules pass mvn test.

[codecov-commenter]

Codecov Report

❌ Patch coverage is 95.12195% with 2 lines in your changes missing coverage. Please review.
✅ Project coverage is 48.99%. Comparing base (051ba27) to head (33c0242).
⚠️ Report is 2 commits behind head on develop.

Files with missing lines	Patch %	Lines
...etmq/broker/lite/LiteSubscriptionRegistryImpl.java	88.88%	1 Missing and 1 partial ⚠️

Additional details and impacted files

@@              Coverage Diff              @@
##             develop   #10386      +/-   ##
=============================================
+ Coverage      48.89%   48.99%   +0.09%     
- Complexity     13452    13495      +43     
=============================================
  Files           1376     1377       +1     
  Lines         100527   100577      +50     
  Branches       12983    12988       +5     
=============================================
+ Hits           49154    49274     +120     
+ Misses         45383    45291      -92     
- Partials        5990     6012      +22     

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