Notification hook with matcher=permission_prompt never triggers

Bug Description

The Notification hook with matcher = "permission_prompt" never triggers, even though the documentation explicitly lists this as an example use case.

Configuration Example

[[hooks]]
event = "Notification"
matcher = "permission_prompt"
command = 'powershell.exe -ExecutionPolicy Bypass -File "C:\Users\zhuzh\.kimi\hooks\windows-toast.ps1" -EventType Permission'
timeout = 10

Root Cause Analysis

1. Where Notification hooks are triggered: src/kimi_cli/soul/kimisoul.py:877-896, inside the deliver_pending("llm") callback. The matcher_value is view.event.type (the notification's type field).

2. Where NotificationEvents are currently created: Only in src/kimi_cli/background/manager.py:525, with type = f"task.{terminal_reason}" (e.g. task.completed, task.failed).

3. Where approval/permission requests live: The ApprovalRuntime in src/kimi_cli/approval_runtime/runtime.py handles permission prompts completely independently from the NotificationManager. It never publishes a NotificationEvent.

4. Documentation inconsistency: Both docs/zh/customization/hooks.md:59-63 and docs/en/customization/hooks.md:59-63 document matcher = "permission_prompt" as a working example, but the code has no implementation for it.

Suggested Fix

Bind NotificationManager to ApprovalRuntime (e.g. in Runtime.__post_init__), and publish a NotificationEvent inside ApprovalRuntime.create_request() with:

• category="system"
• type="permission_prompt"
• source_kind="approval"
• targets=["llm", "wire", "shell"]

This would allow the existing Notification hook pipeline to catch permission prompts and run user-configured commands (e.g. desktop toast notifications).

Read the Notification hook path in src/kimi_cli/soul/kimisoul.py:877-896, event creation in src/kimi_cli/background/manager.py:525, and approval handling in src/kimi_cli/approval_runtime/runtime.py. Trace Runtime.post_init and ApprovalRuntime.create_request(), then compare the documented examples in docs/en/customization/hooks.md and docs/zh/customization/hooks.md. Done means permission prompts publish a permission_prompt NotificationEvent that the existing matcher and hook pipeline can receive.