chore(release): unblock v5.25.1 release

[mashbean]

Summary

• bump matters-server to v5.25.1 so the fix(channel): keep spam out of topic channel feeds #4864 release no longer collides with the existing v5.25.0 tag
• replace deprecated release actions with shell/gh release creation
• make release creation idempotent when a tag already exists

Validation

• parsed .github/workflows/release.yml with Ruby YAML
• verified package.json reports 5.25.1
• confirmed GitHub release v5.25.1 does not exist yet
• confirmed generated changelog range starts at v5.25.0 and includes fix(channel): keep spam out of topic channel feeds #4864

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 73.12%. Comparing base (73dd7a6) to head (715046d).
⚠️ Report is 1 commits behind head on master.

Additional details and impacted files

@@           Coverage Diff           @@
##           master    #4868   +/-   ##
=======================================
  Coverage   73.12%   73.12%           
=======================================
  Files        1081     1081           
  Lines       21641    21641           
  Branches     4735     4735           
=======================================
  Hits        15825    15825           
  Misses       5339     5339           
  Partials      477      477           

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[mashbean]

Status update: CI is green. This PR is the release unblocker for #4864: it bumps package.json to v5.25.1 so the release no longer collides with the existing v5.25.0 tag, and replaces the deprecated release actions with gh release create. Normal merge is currently blocked only by branch protection requiring review.