feat: Complete pipeline hot-rebuild implementation with acceptance tests

- Implements pipeline hot-rebuild with state preservation (issue #43)
- Adds auto-injection of MVP stages for missing capabilities
- Adds radial camera mode for polar coordinate scanning
- Adds afterimage and motionblur effects using framebuffer history
- Adds comprehensive acceptance tests for camera modes and pipeline rebuild
- Updates presets.toml with new effect configurations

Related to: #35 (Pipeline Mutation API epic)
Closes: #43, #44, #45

engine/pipeline/adapters/effect_plugin.py

@@ -6,13 +6,22 @@ from engine.pipeline.core import PipelineContext, Stage
 
 
 class EffectPluginStage(Stage):
-    """Adapter wrapping EffectPlugin as a Stage."""
+    """Adapter wrapping EffectPlugin as a Stage.
 
-    def __init__(self, effect_plugin, name: str = "effect"):
+    Supports capability-based dependencies through the dependencies parameter.
+    """
+
+    def __init__(
+        self,
+        effect_plugin,
+        name: str = "effect",
+        dependencies: set[str] | None = None,
+    ):
         self._effect = effect_plugin
         self.name = name
         self.category = "effect"
         self.optional = False
+        self._dependencies = dependencies or set()
 
     @property
     def stage_type(self) -> str:
@@ -49,7 +58,7 @@ class EffectPluginStage(Stage):
 
     @property
     def dependencies(self) -> set[str]:
-        return set()
+        return self._dependencies
 
     @property
     def inlet_types(self) -> set: