Convert some low-hanging fruit to TypeScript

[sergei-maertens]

Partly closes #445

[codecov]

Bundle Report

Changes will decrease total bundle size by 1.97kB (-0.02%) ⬇️. This is within the configured threshold ✅

Detailed changes

Bundle name	Size	Change
@open-formulieren/sdk-OpenForms-umd	4.9MB	-984 bytes (-0.02%) ⬇️
@open-formulieren/sdk-esm	4.87MB	-988 bytes (-0.02%) ⬇️

Affected Assets, Files, and Routes:

view changes for bundle: @open-formulieren/sdk-esm

Assets Changed:

Asset Name	Size Change	Total Size	Change (%)
assets/sdk-*.js	-982 bytes	1.02MB	-0.1%
assets/index-*.js	-6 bytes	45.46kB	-0.01%

Files in assets/sdk-*.js:

• ./src/components/AppDebug.tsx → Total Size: 1.52kB

• ./src/components/Loader.tsx → Total Size: 672 bytes

• ./src/components/Price.tsx → Total Size: 849 bytes

• ./src/env.ts → Total Size: 536 bytes

• ./src/components/FAIcon.jsx → Total Size: 734 bytes

• ./src/api.ts → Total Size: 4.55kB

• ./src/components/AppDisplay.tsx → Total Size: 928 bytes

• ./src/components/PreviousLink.jsx → Total Size: 682 bytes

• ./src/utils.ts → Total Size: 696 bytes

• ./src/components/Anchor/Anchor.jsx → Total Size: 898 bytes

• ./src/components/Caption.tsx → Total Size: 245 bytes

• ./src/components/forms/SelectField/SelectField.jsx → Total Size: 4.96kB

• ./src/components/Errors/ErrorBoundary.jsx → Total Size: 4.89kB

view changes for bundle: @open-formulieren/sdk-OpenForms-umd

Assets Changed:

Asset Name	Size Change	Total Size	Change (%)
open-*.js	-984 bytes	3.53MB	-0.03%

Files in open-*.js:

• ./src/components/AppDebug.tsx → Total Size: 1.52kB

• ./src/formio/components/Component.js → Total Size: 2.17kB

• ./src/components/PreviousLink.jsx → Total Size: 682 bytes

• ./src/components/Anchor/Anchor.jsx → Total Size: 898 bytes

• ./src/components/Errors/ErrorBoundary.jsx → Total Size: 4.89kB

• ./src/components/AppDisplay.tsx → Total Size: 928 bytes

• ./src/components/FAIcon.jsx → Total Size: 734 bytes

• ./src/components/Price.tsx → Total Size: 849 bytes

• ./src/components/forms/SelectField/SelectField.jsx → Total Size: 4.97kB

• ./src/env.ts → Total Size: 536 bytes

• ./src/api.ts → Total Size: 4.55kB

• ./src/components/Loader.tsx → Total Size: 672 bytes

• ./src/utils.ts → Total Size: 696 bytes

• ./src/components/Caption.tsx → Total Size: 245 bytes

[codecov]

Codecov Report

Attention: Patch coverage is 91.52542% with 5 lines in your changes missing coverage. Please review.

Project coverage is 83.53%. Comparing base (19fc530) to head (7dc4a84).
Report is 9 commits behind head on main.

Files with missing lines	Patch %	Lines
src/api.ts	88.88%	3 Missing ⚠️
src/utils.ts	87.50%	2 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #804      +/-   ##
==========================================
+ Coverage   83.42%   83.53%   +0.10%     
==========================================
  Files         233      233              
  Lines        4633     4633              
  Branches     1180     1193      +13     
==========================================
+ Hits         3865     3870       +5     
+ Misses        738      733       -5     
  Partials       30       30              

Flag	Coverage Δ
storybook	76.86% <88.13%> (+0.04%)	⬆️
vitest	62.27% <80.39%> (+0.09%)	⬆️

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[robinmolen]

Some comments are questions if we want to be strict/specific with the typing. Just take a look and let me know you're thoughts

[robinmolen]

I've added one final comment, but it's not very important. It can be discussed/addressed or you can merge it, both are fine 😄