[codex] Clean up reviewer safety wording after #89

[albertzhzhou-droid]

Summary

Follow-up to already-merged PR #89. This keeps the scope narrow and only cleans up reviewer-facing safety wording.

• Replaces human-facing release snapshot wording with not calibrated for real care.
• Replaces human-facing evidence graph summaries/limitations with the same wording.
• Preserves the existing machine-readable not_clinically_calibrated compatibility key in JSON.
• Adds regression tests so human-facing release snapshot/evidence graph text does not drift back to not clinically calibrated while schema guardrails remain intact.

Validation

• dart format --set-exit-if-changed .
• flutter analyze
• flutter test test/release_snapshot_generator_test.dart test/evidence_graph_builder_test.dart test/local_ai_replay_report_test.dart
• flutter test --concurrency=1 (744 passed)
• npm run public:preflight (0 BLOCKER)
• npm run privacy:preflight (0 blocker)
• git diff --check

Notes

pubspec.lock was touched by Flutter dependency resolution during validation and was restored; it is intentionally not part of this PR.