Implement Apex Agent MVP scaffold

runtime/context.py

@@ -0,0 +1,30 @@
+from __future__ import annotations
+
+from dataclasses import dataclass, field
+from typing import TYPE_CHECKING
+
+from core.models import Scene
+
+if TYPE_CHECKING:
+    from runtime.executor import StepResult
+
+
+@dataclass
+class TaskContext:
+    task_id: str
+    goal: str
+    scenes: list[Scene] = field(default_factory=list)
+    step_results: list["StepResult"] = field(default_factory=list)
+
+    def add_scene(self, scene: Scene) -> None:
+        self.scenes.append(scene)
+
+    def add_step_result(self, result: "StepResult") -> None:
+        self.step_results.append(result)
+
+    @property
+    def latest_scene(self) -> Scene | None:
+        if not self.scenes:
+            return None
+        return self.scenes[-1]
+