gsa: fix login using mismatched client-info (#337)

## What does this PR do?

Fixes #329 (error `-80045` on gsa login).

We were sending client info generated from Android Anisette, but
claiming to be a Mac. Seems like GrandSlam no longer likes this
mismatch.

## How was it tested?

- [x] Run `xtool ds certificates` after updating -> logged out,
provisioning reset
- [x] Re-auth works

## AI tool usage

How much of this PR was AI-assisted? (check one)

- [x] **0** - No AI was used to write code
- [ ] **1** - I was assisted by AI. I reviewed the finished result.
- [ ] **2** - I set the AI going and left it to it; nobody has read the
result - no review, or AI review only

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<!-- This is an auto-generated comment: release notes by coderabbit.ai
-->

## Summary by CodeRabbit

* **Updates**
* Authentication now identifies the client as a Pixel 7 running Android
14 rather than using a macOS-style client description.
* The provider ID is now consistent across platforms. Existing
provisioning may be reset if its saved provider ID differs.
* Before password login, a notice explains the emulated device and
environment, recommends considering a secondary Apple ID, and says
credentials are sent only to Apple.

<!-- end of auto-generated comment: release notes by coderabbit.ai -->

Author: kabiroberai

Sources/XKit/GrandSlam/Anisette/ADIDataProvider.swift

@@ -249,11 +249,7 @@ public struct ADIDataProvider: AnisetteDataProvider {
     }
 
     private static var providerID: String? {
-        #if os(macOS)
-        return "1"
-        #else
-        return nil
-        #endif
+        "2"
     }
 
     public var providerID: String? { Self.providerID }

Sources/XKit/GrandSlam/Anisette/DeviceInfo.swift

@@ -21,7 +21,7 @@ public struct DeviceInfo: Codable, Sendable {
 
         var clientString: String {
             """
-            <\(modelID)> <macOS;27.0;26A5378j> <com.apple.AuthKit/1 (com.apple.akd/1.0)>
+            <Pixel 7> <Android;14;UQ1A.240205.002> <com.apple.AuthKit/1 (com.apple.akd/1.0)>
             """
         }
 

Sources/XToolSupport/AuthCommand.swift

@@ -76,6 +76,12 @@ struct AuthOperation {
     }
 
     private func logInWithPassword() async throws -> AuthToken {
+        print("""
+        Heads up:
+          This works by emulating a Pixel phone/Windows PC to interact with Apple services;
+          consider using a secondary Apple ID. Credentials are only ever sent to Apple.
+        """)
+
         let username = try await Console.promptRequired("Apple ID: ", existing: username)
 
         let password: String