Moving some code around

[olemartinorg]

Description

This is a low-priority PR (conflicts should be reduced before merging this). I'm continuing the ongoing repo and code cleanup by moving some files and code around - in order to hopefully make a more meaningful structure.

In summary:

• The LayoutNode, LayoutPage, LayoutPages and LayoutObect classes has been moved into their own respective source files (out from hierarchy.ts).
• Moving all hooks into their own files, and moving all hook files to src/hooks instead of a combination of src/common/hooks and src/components/hooks.
• Moving everything out of src/shared. Most files, from src/shared/resources has been moved into src/features, where their most closely resembling counterparts reside in the newer repo structure. These 'resources' mostly contain sagas to load app content into the redux store.
• Combining the minor src/sagas, src/reducers and src/store into src/redux. (To reduce the number of small top-level folders, and all of these belong to store/state initialization).

Later additions:

• Moving even more files around (reducing depth of saga files in src/features), thanks to suggestion by @bjosttveit.
• The change above re-introduced problems I saw earlier with saga slices running when being imported, thus causing them to rely on import order to work correctly (some imported values that are not declared yet will be undefined). For that reason, I rewrote all the slices to functions generating slices, and bootstrapped everything in index.tsx so that practically no code starts running until the JS file has been evaluated and all imports are resolved.
• With import order issues resolved, more of the files could be moved into more logical places.

Related Issue(s)

• Architecture: Modularize components using classes and inheritance #377

Verification/QA

• Manual functionality testing
  • I have tested these changes manually
  • Creator of the original issue (or service owner) has been contacted for manual testing (or will be contacted when released in alpha)
  • No testing done/necessary
• Automated tests
  • Unit test(s) have been added/updated
  • Cypress E2E test(s) have been added/updated
  • No automatic tests are needed here (no functional changes/additions)
  • I want someone to help me make some tests
• UU/WCAG (follow these guidelines until we have our own)
  • I have tested with a screen reader/keyboard navigation/automated wcag validator
  • No testing done/necessary (no DOM/visual changes)
  • I want someone to help me perform accessibility testing
• User documentation @ altinn-studio-docs
  • Has been added/updated
  • No functionality has been changed/added, so no documentation is needed
  • I will do that later/have created an issue
• Changes/additions to component properties
  • Changes are reflected in both src/layout/layout.d.ts and layout.schema.v1.json, and these are all backwards-compatible
  • No changes made
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[bjosttveit]

Lots of great changes! Have you considered getting rid of some of the folders containing a single saga-file?

A few examples, but there are many:

[olemartinorg]

@bjosttveit Great point! I didn't go that deeply into it, but I agree with you 100%. I'll check.

[sonarqubecloud]

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35 Code Smells

63.8% Coverage
0.0% Duplication