feat: implement message deletion functionality and improve draft handling

- Added `MoveToTrash` method in `WebmailRepository` to move messages to the Trash folder instead of deleting them permanently.
- Introduced `handleDelete` method in `mailAPI` to handle message deletion requests from the client.
- Updated router to include a new route for message deletion.
- Enhanced the compose page to manage draft integrity, ensuring drafts are correctly associated with sent messages.
- Implemented UI changes to allow users to delete messages from the mail folder view.
- Added tests to verify the correct behavior of message deletion and draft handling.
- Updated database migration scripts to reconcile folder counters and ensure accurate unread counts.
- Added tests for TLS-RPT report parsing and webmail repository functionalities.

services/protocols/internal/presentation/http/router.go

@@ -89,6 +89,7 @@ func (r *Router) registerRoutes() {
 	r.mux.HandleFunc("/api/v1/mail/seen", r.handleMailSeen)
 	r.mux.HandleFunc("/api/v1/mail/send", r.handleMailSend)
 	r.mux.HandleFunc("/api/v1/mail/draft", r.handleMailDraft)
+	r.mux.HandleFunc("/api/v1/mail/delete", r.handleMailDelete)
 	r.mux.HandleFunc("/api/v1/reports/dmarc", r.handleDmarcIngest)
 	r.mux.HandleFunc("/api/v1/reports/tlsrpt", r.handleTlsRptIngest)
 }
@@ -303,6 +304,18 @@ func (r *Router) handleMailSend(w http.ResponseWriter, req *http.Request) {
 	}
 }
 
+// handleMailDelete removes one message. There was no route for this at all,
+// so nothing the webmail displayed could be deleted from it.
+func (r *Router) handleMailDelete(w http.ResponseWriter, req *http.Request) {
+	if req.Method != http.MethodPost && req.Method != http.MethodDelete {
+		writeError(w, http.StatusMethodNotAllowed, "METHOD_NOT_ALLOWED", "POST or DELETE required")
+		return
+	}
+	if r.mailReady(w) {
+		r.mail.handleDelete(w, req)
+	}
+}
+
 func (r *Router) handleMailDraft(w http.ResponseWriter, req *http.Request) {
 	if req.Method != http.MethodPost {
 		writeError(w, http.StatusMethodNotAllowed, "METHOD_NOT_ALLOWED", "POST required")