feat: add phase 3 readonly models

internal/workflow/model.go

@@ -0,0 +1,43 @@
+package workflow
+
+import "codex-agent-manager/internal/runtime"
+
+type View struct {
+	Events       []Event        `json:"events"`
+	HandoffEdges []HandoffEdge  `json:"handoffEdges"`
+	Phases       []Phase        `json:"phases"`
+	Source       SourceEvidence `json:"source"`
+}
+
+type Event struct {
+	Kind       string         `json:"kind"`
+	Label      string         `json:"label"`
+	ThreadID   string         `json:"threadId,omitempty"`
+	RelatedID  string         `json:"relatedId,omitempty"`
+	OccurredAt string         `json:"occurredAt,omitempty"`
+	Source     SourceEvidence `json:"source"`
+}
+
+type HandoffEdge struct {
+	FromThreadID string         `json:"fromThreadId"`
+	ToThreadID   string         `json:"toThreadId"`
+	Label        string         `json:"label"`
+	Source       SourceEvidence `json:"source"`
+}
+
+type Phase struct {
+	Name   string         `json:"name"`
+	Status string         `json:"status"`
+	Source SourceEvidence `json:"source"`
+}
+
+type SourceEvidence struct {
+	Kind       string `json:"kind"`
+	Path       string `json:"path,omitempty"`
+	Confidence string `json:"confidence"`
+	Message    string `json:"message,omitempty"`
+}
+
+type RuntimeReader interface {
+	Snapshot() (runtime.Snapshot, error)
+}