Enhanced PostToolUse Hook Messages

What: Specialized system message types for hook execution outcomes instead of generic informational messages.

Details:

• New message type: post_tool_hook_success for successful hook completion
• New message type: post_tool_hook_cancelled for user-cancelled hooks
• Clearer semantic representation in message history
• Better structured for UI rendering and debugging
• Note: PostToolUse hooks existed in v1.0.113, only the message types are new
• Evidence: PIB() at line 398052, jq0() at line 398064