app/version: bump v1.9 to stable

[obol-platform]

This pull request was automatically generated by the 'Prepare Patch Full Release' GitHub Action.

• Release Branch: main-v1.9
• Version in Code: v1.9
• Tag to be Created: v1.9.3

Changes

• Updated version in app/version/version.go from v1.9-rc to v1.9

Next Steps

1. Review and merge this PR
2. After merge, proceed with "Tag Patch Full Release" workflow to create and push the tag v1.9.3
3. Docker image will be built with tag v1.9.3

category: misc
ticket: none

[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

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 56.53%. Comparing base (5cfb38d) to head (123f7c8).
⚠️ Report is 2 commits behind head on main-v1.9.

Additional details and impacted files

@@              Coverage Diff              @@
##           main-v1.9    #4436      +/-   ##
=============================================
- Coverage      56.62%   56.53%   -0.09%     
=============================================
  Files            237      237              
  Lines          31778    31720      -58     
=============================================
- Hits           17993    17933      -60     
- Misses         11490    11497       +7     
+ Partials        2295     2290       -5     

☔ View full report in Codecov by Sentry.
📢 Have feedback on the report? Share it here.

🚀 New features to boost your workflow:

• ❄️ Test Analytics: Detect flaky tests, report on failures, and find test suite problems.