Windows build: clarify supported MSVC/Visual Studio versions (node-gyp) + avoid postinstall node_modules patches

[DeadWaveWave]

Some contributors report Windows build failures when only VS 2025/2026 Build Tools are installed (MSVC versionMajor=18).

Context

• Our native deps (e.g. better-sqlite3, node-pty) are rebuilt during pnpm install via electron-builder install-app-deps (app-builder-lib -> @electron/rebuild).
• Today we pull @electron/rebuild@4.0.3 -> node-gyp@11.5.0.
• node-gyp@11.5.0's VS detection currently maps versionMajor {15,16,17} -> {2017,2019,2022}. versionMajor=18 is treated as unsupported, and the supported-years list is [2019, 2022].
  • This means VS Build Tools v18 may not be detected.

What we want

• Short term (docs): document Windows prerequisites in CONTRIBUTING.md (VS 2022 Build Tools + Desktop development with C++ workload / Windows SDK) and add a troubleshooting note for VS v18-only setups.
• Long term (proper fix): investigate whether upgrading electron-builder / app-builder-lib / @electron/rebuild (and therefore node-gyp) provides native support for MSVC versionMajor=18, instead of patching node_modules in postinstall.

Non-goals

• We should not ship a postinstall script that mutates files under node_modules/.pnpm/... using string replacement (too brittle across version bumps, and risky cross-platform).

Acceptance

• Clear docs for Windows contributors so pnpm install succeeds.
• If upstream supports MSVC v18, update deps and keep CI green.