fix(build): resolve concurrent-capture errors under Xcode 15.4

Two more latent compile errors surfaced now that Build & Test runs:
- NFCManager.tagReaderSession captured the weak 'self' var inside a
  concurrently-executing Task { @mainactor } (lines 134/135). Bind it once with
  'guard let self' so the Task captures an immutable reference.
- ContactsManager.fetchMTRXContacts captured the mutable 'contacts' var inside a
  Task { @mainactor }. Snapshot it into a 'let' before the Task and return that.

Both are 'reference to captured var ... in concurrently-executing code' errors
under the CI toolchain (Swift 5.10); behavior is unchanged.

Co-authored-by: Dardan <ItsDardanRexhepi@users.noreply.github.com>

Author: cursoragent

Apple/Connectivity/NFCManager.swift

@@ -116,9 +116,10 @@ extension NFCManager: NFCTagReaderSessionDelegate {
         guard let tag = tags.first else { return }
 
         session.connect(to: tag) { [weak self] error in
+            guard let self else { return }
             if let error = error {
-                self?.scanContinuation?.resume(throwing: NFCError.connectionFailed(error.localizedDescription))
-                self?.scanContinuation = nil
+                self.scanContinuation?.resume(throwing: NFCError.connectionFailed(error.localizedDescription))
+                self.scanContinuation = nil
                 return
             }
 
@@ -131,12 +132,12 @@ extension NFCManager: NFCTagReaderSessionDelegate {
             )
 
             Task { @MainActor in
-                self?.lastScannedPayload = payload
-                self?.isScanning = false
+                self.lastScannedPayload = payload
+                self.isScanning = false
             }
 
-            self?.scanContinuation?.resume(returning: payload)
-            self?.scanContinuation = nil
+            self.scanContinuation?.resume(returning: payload)
+            self.scanContinuation = nil
             session.invalidate(errorMessage: "")
         }
     }

Apple/Interaction/ContactsManager.swift

@@ -69,8 +69,9 @@ final class ContactsManager: ObservableObject {
             }
         }
 
-        Task { @MainActor in mtrxContacts = contacts }
-        return contacts
+        let resolved = contacts
+        Task { @MainActor in mtrxContacts = resolved }
+        return resolved
     }
 
     // MARK: - Search