Add option to send replies as original author replica

[LilasKR]

Summary

Adds a new Reply Method option to send fixed-link replies as a replica of the original message author instead of the bot.

This was written with Codex, then tested locally.

Context

Reference: Discord report
https://discord.com/channels/1160873160665731134/1215363563791585350

Changes

• Added a Send as Original Author Replica / Send as %{bot} toggle
• Sends fixed links through a channel webhook when original author replica mode is enabled
• Uses the original message author's display name and avatar for the webhook message
• Disables reply mode when webhook sending is enabled, since webhooks cannot reply
• Falls back to the normal send path if the webhook cannot be created or retrieved
• Keeps original message handling under the existing Original Message setting
• Adds Manage Webhooks permission text, including troubleshooting permissions
• Updates English and Korean locale strings

Tested

Tested locally after adding the setting column to the local test database.

• Bot starts successfully
• Slash commands sync successfully
• Updated locale YAML files parse successfully
• Python syntax checks pass for the touched files

[github-actions]

All contributors have signed the CLA ✍️ ✅
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[LilasKR]

I have read the CLA Document and I hereby sign the CLA

[Kyrela]

Thanks for this pull request. I haven't tested it yet, but I have a couple issues with the code.

Don't hesitate to debate/argue with me if you don't agree with some of my comments, I'm open to discussion.

On another note, did you fully vibe-coded it, and/or are you a developper? More details about the implication of AI in this PR would be appreciated.

[LilasKR]

Thanks for the review!

I’m a UI/UX designer, not a developer. I can read code to some extent, but most of this was vibe-coded with Codex and then adjusted while testing locally.

I agree with most of your points, and I’ll update the PR.

For the typing indicator: I disabled it in webhook mode because the message is sent by a webhook identity instead of the bot user. In my local test, Discord kept showing the bot as typing for a while even after the webhook message had already been sent.

[Kyrela]

Sorry for the late reply, I was quite busy these days. Thank you for your clarification on the usage of AI.

This is better, but there's still a couple things that doesn't seems right. Some of them are important, and some of them are near-nitpicking.

In my local test, Discord kept showing the bot as typing for a while even after the webhook message had already been sent.

You're right, I forgot about this. The typing indicator disappears after 1s or when a message is sent by the "typer". In that case, the "typer" (the bot) never send any message. I guess disabling it is fine in that case. Let's go with it, if that causes problems in the future, I can always put it back