* fix(slack): use SLACK_USER_TOKEN when connecting to Slack (closes#26480)
* test(slack): fix account fixture typing for user token source
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Co-authored-by: Tak Hoffman <781889+Takhoffman@users.noreply.github.com>
Adds support for separate replyToMode settings for DMs vs channels:
- Add channels.slack.dm.replyToMode for DM-specific threading
- Keep channels.slack.replyToMode as default for channels
- Add resolveSlackReplyToMode helper to centralize logic
- Pass chatType through threading resolution chain
Usage:
```json5
{
channels: {
slack: {
replyToMode: "off", // channels
dm: {
replyToMode: "all" // DMs always thread
}
}
}
}
```
When dm.replyToMode is set, DMs use that mode; channels use the
top-level replyToMode. Backward compatible when not configured.
