feat: add workflow node registry phase 2

frontend/src/api/workflows.ts

@@ -101,9 +101,47 @@ export const deleteWorkflow = (id: string): Promise<void> =>
 export const getWorkflowRuns = (workflowId: string): Promise<WorkflowRun[]> =>
   api.get(`/workflows/${workflowId}/runs`).then(r => r.data)
 
-// ─── Pipeline Steps ───────────────────────────────────────────────────────────
+// ─── Node Definitions / Pipeline Steps ───────────────────────────────────────
 
 export type StepCategory = 'input' | 'processing' | 'rendering' | 'output'
+export type WorkflowNodeFieldType = 'number' | 'select' | 'boolean'
+export type WorkflowNodeExecutionKind = 'native' | 'bridge'
+
+export interface WorkflowNodeFieldOption {
+  value: string | number | boolean
+  label: string
+}
+
+export interface WorkflowNodeFieldDefinition {
+  key: string
+  label: string
+  type: WorkflowNodeFieldType
+  description: string
+  section: string
+  default: unknown
+  min: number | null
+  max: number | null
+  step: number | null
+  unit: string | null
+  options: WorkflowNodeFieldOption[]
+}
+
+export interface WorkflowNodeDefinition {
+  step: string
+  label: string
+  category: StepCategory
+  description: string
+  node_type: string
+  icon: string
+  defaults: WorkflowParams
+  fields: WorkflowNodeFieldDefinition[]
+  execution_kind: WorkflowNodeExecutionKind
+  legacy_compatible: boolean
+}
+
+export interface WorkflowNodeDefinitionsResponse {
+  definitions: WorkflowNodeDefinition[]
+}
 
 export interface PipelineStep {
   name: string
@@ -116,6 +154,9 @@ export interface PipelineStepsResponse {
   steps: PipelineStep[]
 }
 
+export const getNodeDefinitions = (): Promise<WorkflowNodeDefinitionsResponse> =>
+  api.get('/workflows/node-definitions').then(r => r.data)
+
 export const getPipelineSteps = (): Promise<PipelineStepsResponse> =>
   api.get('/workflows/pipeline-steps').then(r => r.data)