Adopt TypeScript 5.9

[m-akinc]

Pull Request

📖 Description

Align typescript version to align with Nimble Angular 21 changes and update dependencies.

• Explicitly updated dependencies:
  • typescript 5.9.3
  • eslint v9 (and related deps)
  • @microsoft/api-extractor pinned to v7.59.0 (which aligns to typescript v5.9.3)
• Removed rollup-plugin-filesize
  • Hasn't been updated in a long time and has stale transitive deps
• Consequences of typescript update:
  • switched from "importsNotUsedAsValues": "error" (unsupported since 5.5) to "verbatimModuleSyntax": true
  • removed deprecated "suppressImplicitAnyIndexErrors": true" option (unsupported since 5.5)
    • caused additional type errors to no longer be suppressed. Addressed by either using explicit any types where it made sense locally or added @ts-expect-error statements to address in future refactors (defining better global types, etc
• Consequences of eslint update:
  • migrated old .eslintrc config files to modern, flat configs
  • removed lint rule suppressions that either were already moot, or became moot due to a rule being removed from the "recommended" ruleset (e.g. @typescript-eslint/no-non-null-assertion)
• Switched to package.json of "type": "module"

npm outdated results:

• Downstream Angular version gates: eslint, typescript
• chai requires refactoring
• @types/node aligns with GitHub Actions version
• react should be removed in future update (fast-react not leveraged by nimble-react anymore)
• prettier should be removed in future update (nimble removed prettier and should align)

Package           Current   Wanted   Latest
@eslint/js         9.39.5   9.39.5   10.0.1
@types/chai        4.3.20   4.3.20    5.2.3
@types/chai        4.3.20   4.3.20    5.2.3
@types/chai        4.3.20   4.3.20    5.2.3
@types/chai        4.3.20   4.3.20    5.2.3
@types/chai        4.3.20   4.3.20    5.2.3
@types/node       24.13.3  24.13.3   26.3.0
@types/react      18.3.31  18.3.31  19.2.18
@types/react-dom   18.3.7   18.3.7   19.2.5
chai                4.5.0    4.5.0    6.2.2
chai                4.5.0    4.5.0    6.2.2
chai                4.5.0    4.5.0    6.2.2
chai                4.5.0    4.5.0    6.2.2
chai                4.5.0    4.5.0    6.2.2
eslint             9.39.5   9.39.5   10.9.1
prettier            3.4.2    3.4.2    3.9.6
prettier            3.4.2    3.4.2    3.9.6
prettier            3.4.2    3.4.2    3.9.6
prettier            3.4.2    3.4.2    3.9.6
prettier            3.4.2    3.4.2    3.9.6
prettier            3.4.2    3.4.2    3.9.6
react              18.3.1   18.3.1   19.2.8
react-dom          18.3.1   18.3.1   19.2.8
typescript          5.9.3    5.9.3    7.0.2
typescript          5.9.3    5.9.3    7.0.2
typescript          5.9.3    5.9.3    7.0.2
typescript          5.9.3    5.9.3    7.0.2
typescript          5.9.3    5.9.3    7.0.2
typescript          5.9.3    5.9.3    7.0.2

[rajsite]

To keep TS versions aligned should wait until ready to start merging angular 21 changes to merge