Update Authenticator UI to match Password Manager style

[david-livefront]

🎟️ Tracking

PM-26422

📔 Objective

This PR is the first pass on updating the Authenticator UI to more closely match the Password Manager.

📸 Screenshots

Before	After
Screen_recording_20251002_151314.mp4	Screen_recording_20251002_151059.mp4

⏰ Reminders before review

• Contributor guidelines followed
• All formatters and local linters executed and passed
• Written new unit and / or integration tests where applicable
• Protected functional changes with optionality (feature flags)
• Used internationalization (i18n) for all UI strings
• CI builds passed
• Communicated to DevOps any deployment requirements
• Updated any necessary documentation (Confluence, contributing docs) or informed the documentation team

🦮 Reviewer guidelines

• 👍 (:+1:) or similar for great changes
• 📝 (:memo:) or ℹ️ (:information_source:) for notes or general info
• ❓ (:question:) for questions
• 🤔 (:thinking:) or 💭 (:thought_balloon:) for more open inquiry that's not quite a confirmed issue and could potentially benefit from discussion
• 🎨 (:art:) for suggestions / improvements
• ❌ (:x:) or ⚠️ (:warning:) for more significant problems or concerns needing attention
• 🌱 (:seedling:) or ♻️ (:recycle:) for future improvements or indications of technical debt
• ⛏ (:pick:) for minor or nitpick changes

[github-actions]

Checkmarx One – Scan Summary & Details – fd8c1236-40f8-470e-b58a-bf7703327d28

Great job! No new security vulnerabilities introduced in this pull request

[codecov]

Codecov Report

❌ Patch coverage is 66.98113% with 140 lines in your changes missing coverage. Please review.
✅ Project coverage is 84.53%. Comparing base (9f63ced) to head (0de7658).
⚠️ Report is 5 commits behind head on main.

Files with missing lines	Patch %	Lines
...arden/authenticator/ui/auth/unlock/UnlockScreen.kt	0.00%	30 Missing ⚠️
...icator/feature/navbar/AuthenticatorNavBarScreen.kt	0.00%	28 Missing ⚠️
...i/platform/feature/settings/export/ExportScreen.kt	0.00%	16 Missing ⚠️
...form/feature/settings/importing/ImportingScreen.kt	0.00%	14 Missing ⚠️
...icator/feature/search/VaultVerificationCodeItem.kt	0.00%	13 Missing ⚠️
...enticator/feature/itemlisting/ItemListingScreen.kt	88.00%	8 Missing and 1 partial ⚠️
.../authenticator/feature/search/ItemSearchContent.kt	0.00%	8 Missing ⚠️
...i/authenticator/feature/search/ItemSearchScreen.kt	0.00%	7 Missing ⚠️
...tor/ui/platform/feature/settings/SettingsScreen.kt	94.11%	5 Missing and 1 partial ⚠️
...enticator/feature/search/ItemSearchEmptyContent.kt	0.00%	5 Missing ⚠️
... and 3 more

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #5969      +/-   ##
==========================================
+ Coverage   84.43%   84.53%   +0.09%     
==========================================
  Files         718      717       -1     
  Lines       54782    54627     -155     
  Branches     7526     7505      -21     
==========================================
- Hits        46256    46179      -77     
+ Misses       5888     5818      -70     
+ Partials     2638     2630       -8     

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[david-livefront]

Thanks @SaintPatrck