Summary

• Fix the Messages shared extraction guard regression by using isFiniteNumber(...) instead of direct Number.isFinite(...) in toolbox/messages/messages.js.
• Preserve existing typewriter-speed conversion, fallback, and validation behavior.
• No Sprite Editor, DB/API/schema, or runtime behavior changes intended.

Validation

• PASS: node --check toolbox/messages/messages.js
• PASS: node dev/tools/toolbox-dev/checkSharedExtractionGuard.mjs
• PASS: git diff --check
• FAIL: npm test passes the shared extraction guard, then fails on unrelated missing module src/engine/combat/Combat.js imported by dev/tests/combat/Combat.test.mjs.

Artifact

• dev/workspace/zips/PR_26180_OWNER_004-shared-validation-guard-fix_delta.zip

Merge / Baseline

• Not merged because the requested npm test PASS condition was not met.
• Baseline commit was not created.