[app-attest-env] Log the actual error behind guest-session App Attest failures

Guest session handshake fails silently after the challenge step - no
console output, just a generic "could not load" message in the UI.
DCAppAttestService errors (generateKey/attestKey/generateAssertion)
propagate up uncaught by anything that logs them. Add explicit logging
at each step so the real thrown error is visible instead of debugging
blind.

Sources/PediFoods/Services/GuestSessionService.swift

@@ -93,6 +93,7 @@ actor GuestSessionService {
 
 #if os(iOS)
     private func refreshTokenWithAppAttest() async throws -> String {
+        print("[GuestSessionService] DCAppAttestService.isSupported = \(DCAppAttestService.shared.isSupported), existingKeyId = \(store.appAttestKeyId ?? "nil")")
         guard DCAppAttestService.shared.isSupported else {
             // Simulator can never support App Attest (hardware limitation,
             // not environment-specific) — server has its own documented
@@ -141,9 +142,22 @@ actor GuestSessionService {
     }
 
     private func handshakeWithFreshAttestation(challenge: String) async throws -> String {
-        let keyId = try await DCAppAttestService.shared.generateKey()
+        let keyId: String
+        do {
+            keyId = try await DCAppAttestService.shared.generateKey()
+        } catch {
+            print("[GuestSessionService] generateKey failed: \(error)")
+            throw error
+        }
+
         let clientDataHash = Data(SHA256.hash(data: Data(challenge.utf8)))
-        let attestationObject = try await DCAppAttestService.shared.attestKey(keyId, clientDataHash: clientDataHash)
+        let attestationObject: Data
+        do {
+            attestationObject = try await DCAppAttestService.shared.attestKey(keyId, clientDataHash: clientDataHash)
+        } catch {
+            print("[GuestSessionService] attestKey failed: \(error)")
+            throw error
+        }
 
         let payload = GuestSessionAttestPayload(
             platform: "ios",
@@ -175,7 +189,13 @@ actor GuestSessionService {
 
     private func handshakeWithAssertion(keyId: String, challenge: String) async throws -> String {
         let clientDataHash = Data(SHA256.hash(data: Data(challenge.utf8)))
-        let assertionObject = try await DCAppAttestService.shared.generateAssertion(keyId, clientDataHash: clientDataHash)
+        let assertionObject: Data
+        do {
+            assertionObject = try await DCAppAttestService.shared.generateAssertion(keyId, clientDataHash: clientDataHash)
+        } catch {
+            print("[GuestSessionService] generateAssertion failed: \(error)")
+            throw error
+        }
 
         let payload = GuestSessionAttestPayload(
             platform: "ios",

Sources/PediFoods/Views/Main/PublicLocationPickerView.swift

@@ -161,6 +161,7 @@ struct PublicLocationPickerView: View {
                 errorMessage = "Nenhum estado disponível no momento."
             }
         } catch {
+            print("[PublicLocationPickerView] loadLocations failed: \(error)")
             errorMessage = "Não foi possível carregar. Tente novamente."
         }
         isLoading = false