Reorganizing models, utils and reusable components

[SepidehShahbazi]

The issues #211, #212 and #213 have been completed.

Implemented:

1. Created domain-based component folders as per the proposed structure.
2. Split models.ts and utils.ts into domain-specific files.
3. Identified and documented new models and utils used across the application and added them to the appropriate files.
4. Provided index.ts for models, utils and reusable components.
5. Updated all imports throughout the project to reflect the new directory structure.
6. Tested new changes to ensure no import or rendering issues occur.
7. Transited config folder into the shared folder and added new fileIcons.ts into the config folder for icons which were in the models.ts.
8. Removed reusable pageLoader.tsx. Because it was as the same as LoadingSpinner.tsx.
9. Fixed minor UI bugs.

Minor UI changes:

Before:

1- The color of the LAST ACTIVITY (due to initial data)

2- The height of each row in the Visitor table on the document details page is different from that of other tables.

3-

After:

1-

2-

3-