fix: LEAP-1494: Padding in new textarea is missing in LSO

[ricardoantoniocm]

Ensures padding and border-radius is correct for added textarea regions and corresponding textarea fields

PR fulfills these requirements

• [X] Commit message(s) and PR title follows the format [fix|feat|ci|chore|doc]: TICKET-ID: Short description of change made ex. fix: DEV-XXXX: Removed inconsistent code usage causing intermittent errors
• [ ] Tests for the changes have been added/updated (for bug fixes/features)
• [ ] Docs have been added/updated (for bug fixes/features)
• [ ] Best efforts were made to ensure docs/code are concise and coherent (checked for spelling/grammatical errors, commented out code, debug logs etc.)
• [X] Self-reviewed and ran all changes on a local instance (for bug fixes/features)

Change has impacts in these area(s)

(check all that apply)

• [X] Product design
• [ ] Backend (Database)
• [ ] Backend (API)
• [X] Frontend

What does this fix?

Padding and border radius missing for Textarea component and its results container.

What is the new behavior?

Textarea and results containers now have expected padding and border radius. CSS variables used now have corresponding fallbacks.

Screenshots:

Previous look:

Improved look:

Which logical domain(s) does this change affect?

(for bug fixes/features, be as precise as possible. ex. Authentication, Annotation History, Review Stream etc.) Label Stream, Review Stream and Labeling Configuration

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[ricardoantoniocm]

/git merge

Workflow run Successfully merged: 37 files changed, 282 insertions(+), 88 deletions(-)