Add webhook logging, pagination, middleware, migrations, and prod hardening

- Webhook event logging repo and subscription webhook idempotency
- Pagination helper (echohelpers) with cursor/offset support
- Request ID and structured logging middleware
- Push client improvements (FCM HTTP v1, better error handling)
- Task model version column, business constraint migrations, targeted indexes
- Expanded categorization chain tests
- Email service and config hardening
- CI workflow updates, .gitignore additions, .env.example updates

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

internal/handlers/residence_handler.go

@@ -17,17 +17,19 @@ import (
 
 // ResidenceHandler handles residence-related HTTP requests
 type ResidenceHandler struct {
-	residenceService *services.ResidenceService
-	pdfService       *services.PDFService
-	emailService     *services.EmailService
+	residenceService  *services.ResidenceService
+	pdfService        *services.PDFService
+	emailService      *services.EmailService
+	pdfReportsEnabled bool
 }
 
 // NewResidenceHandler creates a new residence handler
-func NewResidenceHandler(residenceService *services.ResidenceService, pdfService *services.PDFService, emailService *services.EmailService) *ResidenceHandler {
+func NewResidenceHandler(residenceService *services.ResidenceService, pdfService *services.PDFService, emailService *services.EmailService, pdfReportsEnabled bool) *ResidenceHandler {
 	return &ResidenceHandler{
-		residenceService: residenceService,
-		pdfService:       pdfService,
-		emailService:     emailService,
+		residenceService:  residenceService,
+		pdfService:        pdfService,
+		emailService:      emailService,
+		pdfReportsEnabled: pdfReportsEnabled,
 	}
 }
 
@@ -283,6 +285,10 @@ func (h *ResidenceHandler) GetResidenceTypes(c echo.Context) error {
 // GenerateTasksReport handles POST /api/residences/:id/generate-tasks-report/
 // Generates a PDF report of tasks for the residence and emails it
 func (h *ResidenceHandler) GenerateTasksReport(c echo.Context) error {
+	if !h.pdfReportsEnabled {
+		return apperrors.BadRequest("error.feature_disabled")
+	}
+
 	user := c.Get(middleware.AuthUserKey).(*models.User)
 
 	residenceID, err := strconv.ParseUint(c.Param("id"), 10, 32)