chore: add Warden configuration

[Flash0ver]

Summary

Add Warden configuration,
which is picked up by the globally (getsentry organization) installed Warden workflow.

Remarks

Replacement for #5026 and #5024.
Closes #4987.

CI

All getsentry repos have the "Warden" Workflow installed, which requires the ./warden.toml to run.

Workflow run with the configuration of this PR:

• run that found one issue: https://github.com/getsentry/sentry-dotnet/actions/runs/23162658669/job/67294301949
• the comment it produced on this PR: chore: add Warden configuration #5032 (comment)

Local

Warden - with the ./warden.toml configuration - can also be run locally against pending/uncommitted changed, via

npx @sentry/warden

If the Agent Skills have not been installed / updated locally yet, which are mentioned in ./agents.toml, run

npx @sentry/dotagents install

[github-actions]

Semver Impact of This PR

⚪ None (no version bump detected)

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[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 73.92%. Comparing base (a87d441) to head (9da5053).
⚠️ Report is 2 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #5032      +/-   ##
==========================================
+ Coverage   73.71%   73.92%   +0.21%     
==========================================
  Files         497      497              
  Lines       17966    17966              
  Branches     3516     3516              
==========================================
+ Hits        13244    13282      +38     
+ Misses       3858     3830      -28     
+ Partials      864      854      -10     

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[Flash0ver]

note: added by npx @sentry/warden init

I believe this directory contains log files.

[Flash0ver]

note: Agent Skills from https://github.com/getsentry/warden

They were added during npx @sentry/warden init as files in .agents/.
I changed it to use dotagents instead, for consistency.

[Flash0ver]

note:

The above was auto-generated via npx @sentry/warden init.
I added the below via npx @sentry/warden add ... as a first set of review skills that get automatically run

• on CI, via the "global" Warden workflow
• locally, when running npx @sentry/warden against pending/uncommitted changes

[jamescrosswell]

LGTM