* fix: use .js extension for ESM imports of RoutePeerKind
The imports incorrectly used .ts extension which doesn't resolve
with moduleResolution: NodeNext. Changed to .js and added 'type'
import modifier.
* fix tsconfig
* refactor: unify peer kind to ChatType, rename dm to direct
- Replace RoutePeerKind with ChatType throughout codebase
- Change 'dm' literal values to 'direct' in routing/session keys
- Keep backward compat: normalizeChatType accepts 'dm' -> 'direct'
- Add ChatType export to plugin-sdk, deprecate RoutePeerKind
- Update session key parsing to accept both 'dm' and 'direct' markers
- Update all channel monitors and extensions to use ChatType
BREAKING CHANGE: Session keys now use 'direct' instead of 'dm'.
Existing 'dm' keys still work via backward compat layer.
* fix tests
* test: update session key expectations for dmdirect migration
- Fix test expectations to expect :direct: in generated output
- Add explicit backward compat test for normalizeChatType('dm')
- Keep input test data with :dm: keys to verify backward compat
* fix: accept legacy 'dm' in session key parsing for backward compat
getDmHistoryLimitFromSessionKey now accepts both :dm: and :direct:
to ensure old session keys continue to work correctly.
* test: add explicit backward compat tests for dmdirect migration
- session-key.test.ts: verify both :dm: and :direct: keys are valid
- getDmHistoryLimitFromSessionKey: verify both formats work
* feat: backward compat for resetByType.dm config key
* test: skip unix-path Nix tests on Windows
Move mattermost channel implementation from core to extensions/mattermost plugin. Extract config schema, group mentions, normalize utilities, and all mattermost-specific logic (accounts, client, monitor, probe, send) into the extension. Update imports to use plugin SDK and local modules. Add channel metadata directly in plugin definition instead of using getChatChannelMeta. Update package.json with channel and install configuration.
Add Mattermost as a supported messaging channel with bot API and WebSocket integration. Includes channel state tracking (tint, summary, details), multi-account support, and delivery target routing. Update documentation and tests to include Mattermost alongside existing channels.
