chore: rename Tiji→Kangkang test imports + scheme + sync docs

Rename @testable imports across all test/UI test files after the Tiji→Kangkang
project rename in 44ed01a. Add shared scheme. Sync CLAUDE.md / W2 plan / spec
v1.0 to current scope (Symptom feature noted, C1/C2 flow lockdown).

康康/App/KangkangApp.swift

@@ -2,7 +2,7 @@ import SwiftUI
 import SwiftData
 
 @main
-struct TijiApp: App {
+struct KangkangApp: App {
     var sharedModelContainer: ModelContainer = {
         let schema = Schema([
             Indicator.self,

康康/Features/Archive/B1GuideView.swift

@@ -59,7 +59,7 @@ struct B1GuideView: View {
                         .font(.system(size: 12))
                         .foregroundStyle(Tj.Palette.text2)
                         .padding(.top, 2)
-                    Text("所有照片以 AES 加密存于本机沙盒。Tiji 服务端无法访问。")
+                    Text("所有照片以 AES 加密存于本机沙盒。康康 服务端无法访问。")
                         .font(.system(size: 11))
                         .foregroundStyle(Tj.Palette.text2)
                         .lineSpacing(4)