refactor: unify peer kind to ChatType, rename dm to direct (#11881)

* 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

src/infra/outbound/outbound-session.test.ts

@@ -43,7 +43,7 @@ describe("resolveOutboundSessionRoute", () => {
       target: "@alice",
     });
 
-    expect(route?.sessionKey).toBe("agent:main:telegram:dm:@alice");
+    expect(route?.sessionKey).toBe("agent:main:telegram:direct:@alice");
     expect(route?.chatType).toBe("direct");
   });
 
@@ -64,7 +64,7 @@ describe("resolveOutboundSessionRoute", () => {
       target: "user:123",
     });
 
-    expect(route?.sessionKey).toBe("agent:main:dm:alice");
+    expect(route?.sessionKey).toBe("agent:main:direct:alice");
   });
 
   it("strips chat_* prefixes for BlueBubbles group session keys", async () => {
@@ -88,7 +88,7 @@ describe("resolveOutboundSessionRoute", () => {
       target: "123456",
     });
 
-    expect(route?.sessionKey).toBe("agent:main:zalouser:dm:123456");
+    expect(route?.sessionKey).toBe("agent:main:zalouser:direct:123456");
     expect(route?.chatType).toBe("direct");
   });