Remove old SSH feature flags

[quexten]

🎟️ Tracking

📔 Objective

This PR removes old unused feature flags related to ssh keys. These are no longer needed since the feature has been rolled out for over half a year.

📸 Screenshots

⏰ 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

[sonarqubecloud]

Quality Gate passed

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
0.0% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarQube Cloud

[codecov]

Codecov Report

❌ Patch coverage is 0% with 1 line in your changes missing coverage. Please review.
✅ Project coverage is 50.08%. Comparing base (3a6b956) to head (3ffe666).
⚠️ Report is 9 commits behind head on main.

Files with missing lines	Patch %	Lines
src/Api/Vault/Controllers/SyncController.cs	0.00%	0 Missing and 1 partial ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #6400      +/-   ##
==========================================
- Coverage   54.40%   50.08%   -4.33%     
==========================================
  Files        1839     1839              
  Lines       81510    81529      +19     
  Branches     7209     7213       +4     
==========================================
- Hits        44346    40832    -3514     
- Misses      35515    39132    +3617     
+ Partials     1649     1565      -84     

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[github-actions]

Checkmarx One – Scan Summary & Details – f2f0ae48-ed04-43f6-af2b-a493b5293d0d

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