Prepare release 1.0.2

[rantri]

Summary

• advance the managed NuGet package and current compatibility metadata from 1.0.1 to 1.0.2
• promote the merged C++/Python work and managed Linux fixes into the 1.0.2 changelog entry
• synchronize README, packaging, portability, release guidance, and validation expectations
• keep CMake and Python independently versioned at 0.1.0, C ABI at 1.0, mapped layout at 1.2, and resource naming at 1
• upgrade every release-workflow action to an immutable Node 24 commit and add bounded job timeouts

Why

PR #4 added native C++ and Python sibling implementations plus managed Linux compatibility fixes. This preparation change makes those repository changes releasable as managed NuGet patch version 1.0.2 while preserving the independently versioned native and Python publication boundary.

The release workflow still publishes only the managed NuGet package, symbol package, tag, and GitHub release. It does not publish to PyPI or a native package registry.

Publication boundary

This PR does not create tag v1.0.2, publish NuGet 1.0.2, or dispatch the production Release workflow. After this PR is reviewed and merged with green main CI, a maintainer must explicitly run the Release workflow on main with input 1.0.2.

Validation

• full cross-platform release gate: 226 managed tests, all samples, documentation, package consumption, NuGet/symbol packing, and every Docker profile
• native CTest: 5/5, install/export, and clean find_package consumer
• Python: 25 source tests and 27 clean installed-wheel tests, wheel/sdist rebuild, and sample
• interoperability: 62 ordinary tests plus all nine 1,000-value ordered pairs and 10,000 mixed lifecycle cycles
• dotnet format verification
• generated 1.0.2 release-note extraction
• packed NuGet metadata inspection
• official Node 24 runtime verification for all pinned release actions
• confirmed v1.0.2 is unused across Git tags, GitHub Releases, and NuGet.org