Fix SDK-288 tracing auth and diagnostics

[Stephen Belanger (Qard)]

Summary

Implements the bt-owned P0 and P1 work from SDK-288 in issue-level commits:

• SDK-272: make trace enable / trace setup, trace run, and trace import complete from the credentials already available to the command. Environment auth remains invocation-local for run/import; persistent setup materializes the API key into a normal saved profile for future hooks; interactive commands collect a missing key, org, or project instead of requiring a separate login step.
• SDK-274: require explicit consent before ordinary bt login saves BRAINTRUST_API_KEY; the persistent tracing setup command itself is the explicit request to create the durable login it needs.
• SDK-270 / SDK-275: keep bare bt status concise; expand saved profile and credential-storage details only under --all, and show precedence only for an active CLI/environment override.
• SDK-276: clarify that logout is local-only and add a one-confirmation logout --all flow with per-profile JSON results.
• SDK-273: pin the landed daemon revision and provide side-effect-free, credential-redacted auth provenance to bt trace doctor.

Dependency

braintrustdata/braintrust-coding-agent-plugins#32 has landed. This PR pins its squash commit on main (face71d8d758363e881e15310ce79d5fcafa2912).

Validation

• cargo fmt --check
• cargo test --all-targets --locked (757 unit tests, 56 CLI tests, and all dataset, eval, functions, and setup integration suites passed)
• cargo clippy --all-targets --locked -- -D warnings -A clippy::collapsible_match
• git diff --check
• focused regressions prove environment-key persistent setup and explicit-key managed run both complete with saved-profile routes, while environment-key managed run remains invocation-local

Plain cargo clippy --all-targets --locked -- -D warnings is currently blocked by pre-existing collapsible_match findings in unrelated dataset, SQL, and trace TUI code under Rust 1.95; allowing that lint leaves the branch clean.

[github-actions]

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• Workflow run: https://github.com/braintrustdata/bt/actions/runs/33086974676
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