fix: recognize VSCode Agent terminal

[rix0rrr]

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By submitting this pull request, I confirm that my contribution is made under the terms of the Apache-2.0 license

[github-actions]

Dependency Review

✅ No vulnerabilities or license issues or OpenSSF Scorecard issues found.

Scanned Files

None

[codecov-commenter]

Codecov Report

❌ Patch coverage is 40.00000% with 3 lines in your changes missing coverage. Please review.
✅ Project coverage is 88.18%. Comparing base (0920b78) to head (c6a7cbc).
⚠️ Report is 6 commits behind head on main.

Files with missing lines	Patch %	Lines
packages/aws-cdk/lib/cli/util/guess-agent.ts	40.00%	3 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #1540      +/-   ##
==========================================
- Coverage   88.22%   88.18%   -0.05%     
==========================================
  Files          76       76              
  Lines       10820    10839      +19     
  Branches     1488     1493       +5     
==========================================
+ Hits         9546     9558      +12     
- Misses       1246     1253       +7     
  Partials       28       28              

Flag	Coverage Δ
suite.unit	88.18% <40.00%> (-0.05%)	⬇️

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