TRP-915 Updated to Node 24 and resolved vulnerabilities

[samdagnall]

• Updated package.json runtime to Node 24 and removed support for Node 20/22
• Updated github ci workflow to run on Node 24 and removed support for Node 20/22
• Added .nvmrc with version v24.14.0
• Added .npmrc with min-release-age=2 to prevent packages from being installed that are < 2 days old
• Bumped hmpo-cached-model to v7.0.0 with Node 24 support
• Updated sinon and mocha version in package.json
• Added override for serialize-javascript and diff to resolve vulnerabilities
• Changed main field in package.json to point to /lib/index.js

[Copilot]

Pull request overview

Updates this Node library’s runtime/tooling baseline to Node 24 and refreshes dependencies to address reported vulnerabilities.

Changes:

• Bumps Node engine requirement to 24.x and updates CI to run on Node 24 only.
• Updates key dependencies/devDependencies (e.g., hmpo-cached-model, mocha, sinon) and adds npm overrides for vulnerable transitive packages.
• Adds .nvmrc (and intends to add .npmrc policy per PR description).

Reviewed changes

Copilot reviewed 3 out of 5 changed files in this pull request and generated 2 comments.

File	Description
package.json	Updates Node engine, dependency versions, audit command, and adds overrides for vulnerable transitive deps
.nvmrc	Pins local Node version to v24.14.0
.npmrc	Included in PR metadata, but currently empty in the branch snapshot
.github/workflows/ci.yaml	Updates CI matrix to only run on Node 24.x

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[samdagnall]

Tested on a downstream dependency of web-apply running tests. Local testing screenshots have been added to the ticket.

  3647 passing (4s)


=============================== Coverage summary ===============================
Statements   : 100% ( 2202/2202 )
Branches     : 100% ( 1160/1160 )
Functions    : 100% ( 406/406 )
Lines        : 100% ( 2122/2122 )
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File                                    | % Stmts | % Branch | % Funcs | % Lines | Uncovered Line #s 
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> web-apply@1.0.0 posttest
> check-audit --registry='https://registry.npmjs.org'

>>>> npm audit --json --registry https://registry.npmjs.org
Total of 1 actions to process
audit ok.
➜  web-apply git:(CHORE-testing-hmpo-countries-lib-upgrade) ✗