feat(o11y): generate updated clients with populated LRO telemetry attributes

[haphungw]

sidekick was updated to populate telemetry attributes for google-cloud-lro. All new tracing code is gated behind the google_cloud_unstable_tracing flag.

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 97.89%. Comparing base (46ac7d8) to head (8359c0c).
⚠️ Report is 2 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #5629      +/-   ##
==========================================
- Coverage   97.89%   97.89%   -0.01%     
==========================================
  Files         226      226              
  Lines       55536    55536              
==========================================
- Hits        54369    54368       -1     
- Misses       1167     1168       +1     

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[gemini-code-assist]

Code Review

This pull request updates generated code across multiple services to include tracing spans for long-running operation pollers and transitions to a more flexible poller initialization method. It also improves documentation examples for resource identifiers. Feedback identifies that the removal of specific link definitions in doc comments breaks existing references, suggesting a systematic generator issue. Additionally, it is recommended to use more robust tracing patterns like in_scope or .instrument instead of span.enter() to avoid potential issues in asynchronous contexts.