fix: LEAP-433: Fix cursor disappearence issue in labeling interface

[juliosgarbi]

PR fulfills these requirements

• 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.)
• Self-reviewed and ran all changes on a local instance (for bug fixes/features)

Change has impacts in these area(s)

• Product design
• Backend (Database)
• Backend (API)
• Frontend

Describe the reason for change

This PR addresses the cursor disappearance issue observed in the labeling interface, because canvas always has 100% width despite the image size and brushing cursor over the canvas is a grey-ish circle, practically invisible over lightgrey background.

What does this fix?

The proposed solution is to introduce a thin black border around the cursor, enhancing its visibility against varying background contrasts.

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[juliosgarbi]

/git merge develop

Workflow run
Successfully merged: 360 files changed, 907 insertions(+), 822 deletions(-)