feat: add RelationInsight API and wire H5 relation/profile pages

Second P1 growth engine: compare two profiles, gate full tips behind
deep-access mock payment, and list personal archives on /profile.

Co-authored-by: Cursor <cursoragent@cursor.com>

apps/api/cmd/server/main.go

@@ -16,6 +16,7 @@ import (
 	"github.com/yuxingu/digital-psychology/apps/api/internal/middleware"
 	"github.com/yuxingu/digital-psychology/apps/api/internal/repository"
 	"github.com/yuxingu/digital-psychology/apps/api/internal/service/profile"
+	"github.com/yuxingu/digital-psychology/apps/api/internal/service/relation"
 	"github.com/yuxingu/digital-psychology/apps/api/internal/service/report"
 	"github.com/yuxingu/digital-psychology/apps/api/pkg/response"
 )
@@ -32,7 +33,7 @@ func main() {
 	pool, err := db.Connect(ctx, cfg.DatabaseURL)
 	if err != nil {
 		log.Printf("database unavailable: %v", err)
-		log.Printf("hint: docker compose -f deploy/docker-compose.yml up -d")
+		log.Printf("hint: npm run deps:up  (docker-compose.dev.yml)")
 		os.Exit(1)
 	}
 	defer pool.Close()
@@ -46,11 +47,13 @@ func main() {
 		os.Exit(1)
 	}
 
-	profileSvc := &profile.Service{Repo: &repository.ProfileRepo{Pool: pool}}
-	reportSvc := &report.Service{
-		Profiles: &repository.ProfileRepo{Pool: pool},
-		Reports:  &repository.ReportRepo{Pool: pool},
-	}
+	profileRepo := &repository.ProfileRepo{Pool: pool}
+	reportRepo := &repository.ReportRepo{Pool: pool}
+	relationRepo := &repository.RelationRepo{Pool: pool}
+
+	profileSvc := &profile.Service{Repo: profileRepo}
+	reportSvc := &report.Service{Profiles: profileRepo, Reports: reportRepo}
+	relationSvc := &relation.Service{Profiles: profileRepo, Reports: reportRepo, Relations: relationRepo}
 
 	r := gin.New()
 	r.Use(gin.Recovery(), gin.Logger(), middleware.RequestID())
@@ -69,6 +72,7 @@ func main() {
 	authed.Use(middleware.DeviceAuth(pool))
 	(&handler.ProfileHandler{Svc: profileSvc}).Register(authed)
 	(&handler.ReportHandler{Svc: reportSvc}).Register(authed)
+	(&handler.RelationHandler{Svc: relationSvc}).Register(authed)
 
 	log.Printf("yuxingu api listening on %s env=%s", cfg.HTTPAddr, cfg.AppEnv)
 	if err := r.Run(cfg.HTTPAddr); err != nil {