[frontend] Migrate away from deprecated Grid

[imnasnainaec]

Notes for review:

• In most places, replaced <Grid> with <Grid2>, <Stack>, <Box>, <div>, or nothing, as fit the design need.
• <Stack direction="row"> can be used in place of <Grid2> when we don't want the items in the row to wrap to a second row in a narrow window
• Replaced the <Grid>/<List> combo with a <Table> in DomainStatistics & UserStatistics components
• <Card> layout was made more consistent across InvalidLink, Login, Signup, ResetRequest, & PasswordReset
• Moved Save and Cancel buttons from bottom of CharInv into child component CharacterEntry at top
• Do a side-by-side visual comparison between this and master (on QA) to make sure appearance is (roughly) the same or (subjectively) improved on all edited components
• Try each edited component with various window widths > 300px (we don't care about narrower than that)
• Click "Forgot password?" on the Login page to test ResetRequest; initiate a password reset and click the link sent to your email to test PasswordReset; change a character in the token within that url to test InvalidLink
• To test UploadImage and ViewImageDialog (respectively):
  • go to project settings > "Users" tab > "Manage speakers", add a speaker, click the + preceding the speaker name, select "Upload image consent"
  • click the "Browse" button and select any image file from your computer, click the "Save" button, click the image icon preceding the speaker name (where the + used to be)
• Test *Completed components by clicking a completed goal tile in Data Cleanup under "You've completed:"
  • For CharInvCompleted, first go to Data Cleanup > Create Character Inventory, click on any character tile with multiple occurrences, and do a Find & Replace
  • For MergeDupsCompleted, first go to Data Cleanup > Merge Duplicates, and merge and/or delete words in various combinations
  • For WordCard and ReviewEntriesCompleted, first go to Data Cleanup > Review Entries and edit several entries, including adding multiple semantic domains to a sense
• Test SiteSettings by logging in with a site admin (https://github.com/sillsdev/TheCombine?tab=readme-ov-file#grant-admin-rights), then click your avatar to open the UserMenu and the top option will be "Site Settings"

This change is 

[codecov]

Codecov Report

Attention: Patch coverage is 54.30464% with 69 lines in your changes missing coverage. Please review.

Project coverage is 72.90%. Comparing base (8c6b909) to head (723d34f).

Files with missing lines	Patch %	Lines
...rc/components/ProjectSettings/ProjectLanguages.tsx	65.38%	8 Missing and 1 partial ⚠️
...onents/DataEntry/DataEntryTable/NewEntry/index.tsx	33.33%	6 Missing ⚠️
src/components/InvalidLink/index.tsx	0.00%	4 Missing ⚠️
...s/ProjectSettings/ProjectSchedule/DateSelector.tsx	0.00%	4 Missing ⚠️
...ts/SiteSettings/UserManagement/ConfirmDeletion.tsx	0.00%	4 Missing ⚠️
...oals/CharacterInventory/CharInv/CharacterEntry.tsx	77.77%	4 Missing ⚠️
...riesTable/Cells/EditCell/EditSensesCardContent.tsx	55.55%	4 Missing ⚠️
src/components/Buttons/UndoButton.tsx	25.00%	3 Missing ⚠️
src/components/Login/Login.tsx	50.00%	3 Missing ⚠️
src/components/PasswordReset/ResetPage.tsx	50.00%	3 Missing ⚠️
... and 15 more

Additional details and impacted files

@@            Coverage Diff             @@
##           master    #3787      +/-   ##
==========================================
- Coverage   72.92%   72.90%   -0.03%     
==========================================
  Files         286      286              
  Lines       10771    10764       -7     
  Branches     1340     1344       +4     
==========================================
- Hits         7855     7847       -8     
- Misses       2516     2518       +2     
+ Partials      400      399       -1     

Flag	Coverage Δ
backend	81.91% <ø> (ø)
frontend	65.81% <54.30%> (-0.06%)	⬇️

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