feat(server): start and stop groups of rules via tags

[Elia-Renzoni]

This PR implements the ability to start and stop groups of rules via REST APIs by leveraging the existing rule tagging feature.

The original issue requested the ability to start or stop all rules in a group when calling REST APIs. rule tags were identified as a natural and flexible way to represent rule groups. This approach was discussed and agreed upon in the issue.

What's New:

• REST endpoint to start rules by tag.
• REST endpoint to stop rules by tag.
• Support for operating on multiple rules in a single request.
• No new grouping concept introduced, existing tags are reused.

The test may be flaky and might require further stabilization. Overall, this implementation is intended as a proof of concept to validate the approach and gather feedback before further refinements.

Related Issue: #1822

[codecov]

Codecov Report

❌ Patch coverage is 39.62264% with 32 lines in your changes missing coverage. Please review.
✅ Project coverage is 71.88%. Comparing base (ef0cb4d) to head (de9cb46).
⚠️ Report is 4 commits behind head on master.

Files with missing lines	Patch %	Lines
internal/server/rule_tag.go	37.25%	26 Missing and 6 partials ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##           master    #3968      +/-   ##
==========================================
+ Coverage   71.87%   71.88%   +0.01%     
==========================================
  Files         456      456              
  Lines       52578    52656      +78     
==========================================
+ Hits        37787    37849      +62     
- Misses      11867    11884      +17     
+ Partials     2924     2923       -1     

☔ 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.

[Elia-Renzoni]

I’ll fix the issues as soon as possible