fix: drop Node 18/20 support, require >=22 @W-23388103@

[WillieRuemmele]

Summary

• Bump engines.node from >=18.0.0 to >=22.0.0
• Node 18 reached EOL September 2025, Node 20 reached EOL April 2026
• Fresh installs already crash on Node 18/20 due to @jsforce/jsforce-node@3.10.17 pulling undici@^8.5.0 (requires Node >=22)
• Drop win32-x86 (32-bit Windows) build by passing --targets win32-x64,win32-arm64 to pack:win. The standalone builds move to Node 24, which no longer ships 32-bit Windows binaries. Telemetry shows 32-bit Windows is ~0.01% of CLI usage (~350 machines), and ~84% of those were already on EOL Node and non-functional on current releases.

Fixes forcedotcom/cli#3596
Related forcedotcom/cli#3603

Work Item

@W-23388103@: [CLI] Use node v24, deprecate 18 and 20

Merge / sequencing note

The win32-x86 removal pairs with bundling Node 24 (deleting the NODE_VERSION_OVERRIDE repo variable, or setting it to 24.x). Node 24 has no win-x86 binary. Note: oclif already auto-skips win32-x86 when the bundled Node is >24.0.0, so the explicit --targets flag makes the intent clear and also drops x86 while still pinned to Node 22. After merge + var deletion, trigger a nightly and confirm only x64/arm64 Windows tarballs upload.

Test plan

• CI passes on Node 22 and 24 (already the case — CI has not tested 18/20 since they went EOL)
• npm install on Node <22 shows engines warning
• Post-merge: nightly builds only win32-x64 and win32-arm64, no x86 pack failure

[WillieRuemmele]

Closing — changing our approach to dropping Node 18/20 support (W-23388103). This declarative engines-only bump is being superseded; a new strategy will follow. Not merging this PR.