release: stabilize 1.0.0 release gates

[SunSi12138]

Summary

• stabilize deterministic race-test coordination under loaded GitHub runners
• preserve all assertions and production behavior
• complete the final SharpLink 1.0.0 release gate on the exact integration history

Evidence

• local Unit Tests: 513/513 passed in eight consecutive Release runs across the two commits
• dev PR test: stabilize release race coordination #28 Quick and CodeQL: passed
• product assemblies and package metadata are unchanged from the reviewed 1.0.0 candidate