feat(discord): Components support

[DeanMauro]

Summary

What

Adds opt-in support for Discord Components.

Why

Discord Components allows developers more control over the layout of bot messages by treating text, images, files, and buttons as flexible components. Instead of the rigid text-above-embeds layout, elements can be arranged in any order or column.

An extreme example of what's possible with Components:

How

Embeds remain the default behavior. The Discord adapter now supports a componentsV2 flag to
When enabled, card messages render with Discord Components v2 containers, sections, text displays, media galleries, separators, buttons, and string selects, and include the IS_COMPONENTS_V2 message flag.

Test plan

Create a Chat with the Discord adapter. Set contentFormat: DiscordContentFormat.ComponentsV2 and create a post that uses sections, markdown, buttons, etc. Note that

1. All elements should render correctly.
2. Individual sections can contain their own actions.
3. Markdown formatting gets rendered correctly.

import { Actions, Button, Card, CardText, Image, LinkButton, Section } from "chat";
import { createDiscordAdapter } from "@chat-adapter/discord";

const discord = createDiscordAdapter({
  contentFormat: DiscordContentFormat.ComponentsV2,
});

await thread.post(
  <Card title="Deployment ready" subtitle="Production build completed">
    <Section>
      <CardText>
        **Version 2.4.0** is ready to promote.

        Review the release notes, then choose an action below.
      </CardText>
      <Image url="https://example.com/deploy-preview.png" alt="Preview" />
    </Section>

    <Actions>
      <Button id="promote" style="primary">
        Promote
      </Button>
      <Button id="rollback" style="danger">
        Roll back
      </Button>
      <LinkButton url="https://example.com/deployments/123">
        View deployment
      </LinkButton>
    </Actions>
  </Card>
);

Checklist

• All commits are signed and verified
• All commits are signed off for the DCO (git commit -s)
• pnpm validate passes
• Changeset added (or N/A — see CONTRIBUTING.md)
• Documentation updated (or N/A)

[vercel]

@DeanMauro is attempting to deploy a commit to the Vercel Team on Vercel.

A member of the Team first needs to authorize it.

[DeanMauro]

@dancer @cramforce I have another one for you. Components unlock a lot more flexibility over embeds in how messages can be laid out.

After this, I'll handle modal support.