hermes - 💡(How to fix) Fix Discord clicked slash-command suggestions are not normalized before dispatch

Bug

Clicked Discord slash-command suggestions can arrive in message content as Discord application-command mentions such as </status:123456789> instead of literal /status text.

Hermes command detection currently expects a literal leading slash, so a clicked suggestion can fall through as an unknown/unrecognized command even though manually typing the same slash command works.

Reproduction

1. In Discord, use/click an application command suggestion such as /status.
2. Discord delivers message content shaped like </status:123456789>.
3. Hermes receives the message and does not normalize it to /status before command dispatch.

Expected

Hermes should normalize Discord application-command mentions back to plain slash command text before command detection.

Examples:

• </status:123456789> -> /status
• @bot </status:123456789> -> /status after bot mention stripping

Proposed fix

Normalize application-command mention payloads before command detection, both before and after bot mention stripping, and add regression coverage for clicked Discord command suggestions with and without arguments.

Relevant files from the closed PR draft:

• gateway/platforms/discord.py
• tests/gateway/test_discord_slash_commands.py

Originally proposed as PR #29508, now converted to an issue to avoid maintaining a contributor fork.