pr05 Typescript Migration: Update client/common folder to use the barrel folder structure

[clairep94]

Proposing to update the common folder (and future folders with react components) to use the barrel folder structure:

/client
  /common
    /Button
      Button.tsx
      Button.test.tsx
      Button.storybook.ts
      Button.styles.ts
      Button.types.ts
      index.ts <---- Exports the non-test files above

Benefits:

• Improves Maintainability: When internal file structure changes, only the barrel files need to be updated, keeping import paths stable across the codebase.
• Enhances Discoverability: Barrels act as a directory index, making it easy to see and understand what modules a folder exposes.
• Encourages Consistency: Enforces a consistent module organization and import pattern across teams and contributors.
• Facilitates Tree Shaking: When set up properly with ES modules, unused exports can be eliminated during bundling, improving app size.

Changes:
Move the following to barrel structure after PR processing#3565

I have verified that this pull request:

• has no linting errors (npm run lint)
• has no test errors (npm run test)
• is from a uniquely-named feature branch and is up to date with the develop branch.
• is descriptively named and links to an issue number, i.e. Fixes #123