init 5S article and refacto pull system

src/modules/pull-system/feature/feature.ts

@@ -0,0 +1,10 @@
+export type FeatureStatus = 'doing' | 'done'
+
+export type Feature = {
+  name: string
+  complexity: number
+  leadTime: number
+  status: FeatureStatus
+  step: number
+  qualityIssue: number
+}