fix(459): 🐛 fix claude code env var bug

[SeanAlexanderHarris]

corrects a fat finger error in the claude code env var that should not include an underscore

[prolific-snyk]

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[Copilot]

Pull request overview

Updates the agent-environment detection used for composing the CLI User-Agent header by correcting the Claude Code environment variable name (removing the underscore) and aligning related tests.

Changes:

• Rename the Claude Code detection env var from CLAUDE_CODE to CLAUDECODE.
• Update agent detection source list to use the corrected env var.
• Adjust unit tests that isolate/seed agent env vars to match the new name.

Reviewed changes

Copilot reviewed 3 out of 3 changed files in this pull request and generated 1 comment.

File	Description
client/client_test.go	Updates user-agent composition tests to use CLAUDECODE when simulating an agent-driven environment.
agentenv/agentenv.go	Switches the Claude Code detection source env var to CLAUDECODE.
agentenv/agentenv_test.go	Updates agent detection tests to use CLAUDECODE and keeps isolation of known agent env vars consistent.