[UX] Add first-class false-positive reporting for safety guardrail blocks

Problem

Claude Code safety-guardrail false positives are currently hard for users to report in a useful, private, triageable way.

When a benign local-development request is blocked with "This request triggered safety guardrails" or a cyber-safeguards/CVP message, the user-facing path points users toward support/CVP forms. In practice, that path can become generic, duplicated, or unmonitored, while the information Anthropic needs most - request ID, model, Claude Code version, session metadata, and a sanitized explanation of intent - is not gathered in one structured flow.

This creates two bad outcomes:

1. Users scatter reports across GitHub issues, support chat, email, and social media to be heard.
2. Anthropic receives less consistent data for tuning the classifier.

Related public examples include #62190 and #64230, but the request here is specifically about the reporting path, not just one false-positive cluster.

Proposed behavior

Add a first-class false-positive reporting action to Claude Code whenever a safety-guardrail block occurs.

For example:

• A "Report false positive" action directly in the error banner.
• A CLI command such as /report-false-positive or claude doctor --report-guardrail.
• Automatic capture of safe diagnostic metadata: request ID, model, Claude Code version, platform, timestamp, and the exact block type.
• A private text field where the user can explain why the task was benign.
• Optional local attachment support for sanitized logs or excerpts.
• A clear confirmation that the report reached the right triage path and whether a human review is expected.

Privacy / safety expectations

The report should be private to Anthropic, not posted publicly. It should avoid exposing local paths, source code, credentials, or personal data by default. If request IDs are needed publicly for support, the UI should say so explicitly; otherwise they should be routed privately.

Why this matters

False-positive guardrail blocks are especially disruptive in Claude Code because the user is often in the middle of local development work, debugging, log review, testing, or defensive security review. A built-in report path would reduce duplicate public issues, reduce user frustration, and give Anthropic cleaner data for classifier tuning.