fix: drop .ts extensions from primitives imports

Use extensionless import specifiers in project.ts and work.ts so the
modules resolve under Node ESM and bundler resolution, consistent with
allowImportingTsExtensions on the consuming packages.

packages/primitives/src/project.ts

@@ -1,9 +1,9 @@
 /* eslint-disable max-classes-per-file -- deep Effect v4 domain module: branded schemas, tagged errors, and context services */
 import { Context, Effect, Layer, Schema } from "effect";
 
-import { OrganizationId, ProjectId, TimestampMs } from "./signal.ts";
+import { OrganizationId, ProjectId, TimestampMs } from "./signal";
 
-export type { OrganizationId, ProjectId } from "./signal.ts";
+export type { OrganizationId, ProjectId } from "./signal";
 
 // ---------------------------------------------------------------------------
 // Domain constants

packages/primitives/src/work.ts

@@ -1,7 +1,7 @@
 import { Array as EffectArray, Effect, Order, Schema } from "effect";
 
-export { WorkStatus } from "./work-lifecycle.ts";
-export type { WorkStatus as WorkLifecycleStatus } from "./work-lifecycle.ts";
+export { WorkStatus } from "./work-lifecycle";
+export type { WorkStatus as WorkLifecycleStatus } from "./work-lifecycle";
 
 const MeaningfulString = Schema.String.check(
   Schema.makeFilter((value) => value.trim().length > 0, {