domain: add Processing entities and ports (Job, JobBatch, Plugin, Pipeline)

crates/domain/src/entities/processing_pipeline.rs

@@ -0,0 +1,35 @@
+use crate::value_objects::{StructuredData, SystemId};
+
+#[derive(Debug, Clone, serde::Serialize, serde::Deserialize)]
+pub struct PipelineStep {
+    pub plugin_id: SystemId,
+    pub step_order: u32,
+    pub configuration: StructuredData,
+}
+
+#[derive(Debug, Clone, serde::Serialize, serde::Deserialize)]
+pub struct ProcessingPipeline {
+    pub pipeline_id: SystemId,
+    pub trigger_event: String,
+    pub steps: Vec<PipelineStep>,
+}
+
+impl ProcessingPipeline {
+    pub fn new(trigger_event: impl Into<String>) -> Self {
+        Self {
+            pipeline_id: SystemId::new(),
+            trigger_event: trigger_event.into(),
+            steps: Vec::new(),
+        }
+    }
+
+    pub fn add_step(&mut self, plugin_id: SystemId, config: StructuredData) {
+        let next_order = self.steps.iter().map(|s| s.step_order).max().unwrap_or(0)
+            + if self.steps.is_empty() { 0 } else { 1 };
+        self.steps.push(PipelineStep {
+            plugin_id,
+            step_order: next_order,
+            configuration: config,
+        });
+    }
+}