feat: implement DCOS source tree, tests, and build configuration

Complete implementation of the DCOS package including:
- 40+ Python source files across agents, communication, core, learning, memory, protocols, utils
- pyproject.toml build configuration
- 102 unit tests across all subsystems
- Fixed flake.nix (Python 3.12, proper dependencies, pyproject build)
- Fixed .woodpecker.yml (correct paths, removed silent-fail flags)
- Added .gitignore
- Cleared stale pytest cache

tests/test_core/test_scheduler.py

@@ -0,0 +1,51 @@
+"""
+Tests for the TaskScheduler.
+"""
+
+import pytest
+from dcos.core.scheduler import TaskScheduler, Task
+
+
+class TestTaskScheduler:
+    def test_enqueue_dequeue(self):
+        scheduler = TaskScheduler()
+        task = Task(name="test", agent_id="agent_1", priority=5)
+        scheduler.enqueue(task)
+        dequeued = scheduler.dequeue()
+        assert dequeued is not None
+        assert dequeued.name == "test"
+        assert dequeued.status.name == "RUNNING"
+
+    def test_priority_ordering(self):
+        scheduler = TaskScheduler()
+        t1 = Task(name="low", agent_id="a1", priority=1)
+        t2 = Task(name="high", agent_id="a2", priority=10)
+        scheduler.enqueue(t1)
+        scheduler.enqueue(t2)
+        first = scheduler.dequeue()
+        assert first is not None and first.name == "high"
+
+    def test_complete_task(self):
+        scheduler = TaskScheduler()
+        task = Task(name="done", agent_id="a1")
+        scheduler.enqueue(task)
+        dequeued = scheduler.dequeue()
+        assert dequeued is not None
+        result = scheduler.complete(dequeued.id)
+        assert result is True
+
+    def test_dependency_wait(self):
+        scheduler = TaskScheduler()
+        dep = Task(name="dependency", agent_id="a1")
+        main = Task(name="main", agent_id="a2", depends_on=[dep.id])
+        scheduler.enqueue(dep)
+        scheduler.enqueue(main)
+        # Only dep should dequeue since main depends on dep
+        first = scheduler.dequeue()
+        assert first is not None and first.name == "dependency"
+        second = scheduler.dequeue()
+        assert second is None  # main still blocked
+
+    def test_empty_queue(self):
+        scheduler = TaskScheduler()
+        assert scheduler.dequeue() is None