Keep zarvis approvals out of minibuffer

[edwin-zvs]

Summary

• keep zarvis-originated tool approvals out of the global TUI minibuffer prompt
• stop forwarding tool approval requests as orchestrator/operator observations
• update approval-mode docs so inline approval prompts are the canonical interaction surface

Details

Zarvis already renders risky-tool approval inline in the session PTY, where the user can answer with the approval key. The TUI was also opening a global ApproveTool minibuffer prompt for selected zarvis sessions, and the orchestrator observer could surface approval requests as operator observations.

This changes the TUI to skip the global approval minibuffer for sessions that render approvals inline (zarvis and the orchestrator session). It also removes ToolApprovalRequest from the orchestrator observer allow-list so background approvals do not show up in the operator/minibuffer surface.

Tests

• cargo test -p agentd-cli approval_prompt -- --nocapture
• cargo test -p agentd-adapter-zarvis observe -- --nocapture
• git diff --check
• cargo build