feat: copper accent theme, always-expanded group filter, app icon; rename MyPass to KeeVault

- Custom copper AccentColor and warm VaultBackground color assets (light/dark),
  applied to both the main app and the AutoFill extension (which needed its own
  copy of the asset catalog plus ASSETCATALOG_COMPILER_GLOBAL_ACCENT_COLOR_NAME
  and an explicit .tint() modifier, since extensions don't pick up the app-wide
  accent color the same way a full SwiftUI App/Scene does).
- GroupFilterView no longer uses DisclosureGroup for subgroups -- the whole tree
  renders always-expanded (indented per depth) so active filters are visible at
  a glance instead of requiring tap-to-expand.
- Added a placeholder app icon (padlock glyph, light/dark/tinted variants plus
  macOS sizes) -- previously the icon slot existed but had no actual images,
  which blocks App Store/TestFlight archive validation.
- Added ITSAppUsesNonExemptEncryption = NO (standard encryption only, via
  KeePassKit) to skip the export-compliance prompt on each upload.
- Renamed the app from MyPass to KeeVault throughout: Xcode project/targets/
  schemes, the MyPassCore package (now KeeVaultCore) and every import site,
  folder and file names, bundle identifiers (org.antiloop222.keevault) and
  their App Group/Keychain-group entitlements, and remaining UI/string
  references -- MyPass was already taken as an App Store app name.

AutoFill/Views/ExtensionUnlockView.swift

@@ -1,7 +1,7 @@
 // AutoFill/Views/ExtensionUnlockView.swift
 import SwiftUI
 import Combine
-import MyPassCore
+import KeeVaultCore
 
 /// Root view for the extension -- shows unlock screen or credential list depending on state.
 struct ExtensionRootView: View {
@@ -36,7 +36,8 @@ struct ExtensionRootView: View {
                     CredentialListView(vm: vm)
                 }
             }
-            .navigationTitle("MyPass")
+            .background(Color("VaultBackground"))
+            .navigationTitle("KeeVault")
             .navigationBarTitleDisplayMode(.inline)
             .toolbar {
                 ToolbarItem(placement: .cancellationAction) {
@@ -44,6 +45,7 @@ struct ExtensionRootView: View {
                 }
             }
         }
+        .tint(Color("AccentColor"))
         .task { await vm.tryBiometricUnlock() }
     }
 
@@ -74,8 +76,8 @@ struct ExtensionRootView: View {
             }
 
             if !vm.hasVault || vm.errorMessage != nil {
-                Link(destination: URL(string: "mypass://unlock")!) {
-                    Label("Open MyPass to set up vault", systemImage: "arrow.up.right")
+                Link(destination: URL(string: "keevault://unlock")!) {
+                    Label("Open KeeVault to set up vault", systemImage: "arrow.up.right")
                         .font(.caption)
                 }
             }
@@ -140,7 +142,7 @@ final class ExtensionViewModel: ObservableObject {
         guard canUseBiometrics, session.isLocked else { return }
         isUnlocking = true
         do {
-            try await biometricService.authenticate(reason: "Unlock MyPass")
+            try await biometricService.authenticate(reason: "Unlock KeeVault")
             try performUnlockFromKeychain()
         } catch {
             errorMessage = error.localizedDescription