[codex] Consolidate announce handling and stress validate release

[brothercorvo]

Summary

• Consolidates REM announce handling around LXMF-rs/LXMF SDK announce encoding, parsing, delivery announce interpretation, and SDK announce normalization.
• Keeps REM-specific announce policy local: capability classification, saved-peer decisions, UI projection, and mission workflow semantics.
• Adds stress_test.md release evidence and updates Android native/generated artifacts for the verified release build.

Stress Test / Live Validation

• Three USB phones validated with the release APK installed.
• Startup readiness, Chat, EAM, Event/MECP, checklist replication, receiver restart persistence, and SOS visibility were exercised.
• SOS visibility was confirmed on both target phones by the operator.
• SOS receiver-restart survival was explicitly skipped by operator direction for this finalization pass.
• Announce identity spot check is recorded: Phone B observed the temporary identity, Phone C remained READY and received other announce traffic but did not log that temporary identity during the bounded window, and Phone A was restored to Pixel.

Verification

• cargo fmt --manifest-path crates/reticulum_mobile/Cargo.toml -- --check
• node apps/mobile/src/utils/readinessErrors.test.mjs - 11/11 passed
• cargo test --manifest-path crates/reticulum_mobile/Cargo.toml -- --test-threads=1 - 258/258 passed
• git diff --cached --check