Signal 提及占位符  替换为可读 @uuid/@phone（PR #2013）

• Signal channel integration is enabled and mention-heavy messages are part of your workflow.
• You can test with at least two mentions in one message to validate index handling.

1. Upgrade to runtime containing PR #2013 and restart gateway.
2. Send Signal test message with multiple mentions and mixed plain text.
3. Inspect parsed message text and confirm placeholder characters are replaced with @uuid/@phone.
4. Verify replacement order is reverse-index to avoid offset shift corruption.
5. Run a regression where no mentions exist to ensure plain text path remains unchanged.

• @uuid/@phone is a technical identifier, not always a friendly display name.
• Different Signal bridge versions may expose mention metadata differently（需验证）。

This tip is aggregated from community/public sources and preserved with attribution.