chore(deps): upgrade node to 22 and do some cleaning

[cheefbird]

Context

aligning limble-tree with the rest of the org's repos (webapp, flannel) on node 22. also took the opportunity to remove dead deps/scripts and patch vulnerable transitive deps.

Changes Made

• .nvmrc → 22.22
• package.json engines → node >=22.22 <23, npm >=10.9.4
• CI workflow (pullRequestChecks.yml) → node-version: "22" across all three jobs
• removed unused devDeps: eslint-watch, @angular-eslint/builder
• removed dead start script (broken in monorepo anyway, dev:sandbox is the real one)
• added overrides for tar and serialize-javascript to patch known vulns
• bumped angular deps to latest 19.2.x patch via ng update
• lockfile regenerated on node 22 (lockfileVersion 2 → 3)

Testing Notes

• npm ci succeeds on node 22
• npm run check passes (lint + format + build + tests)
• npm run dev:sandbox serves correctly
• npm audit shows no high/critical vulns
• CI passes on the PR