Fetch bootstrap data uncached so manifest hash diffs always self-heal

Sources/core/Managers/NetworkManager.swift

@@ -12,18 +12,30 @@ public final class NetworkManager {
 
     private init() {}
 
+    /// Session that never serves cached responses. Bootstrap data must reflect ORIGIN
+    /// truth on every run: management.json drives the per-item hash check, so a stale
+    /// manifest (from the local URL cache or a CDN edge that hasn't purged yet) makes a
+    /// changed file — e.g. ProvisioningWatcher.sh — compare against a stale expected hash,
+    /// get judged "already valid", and never re-download. Disabling the URL cache and
+    /// ignoring local + remote caches makes the hash diff always self-heal.
+    private static let noCacheSession: URLSession = {
+        let config = URLSessionConfiguration.default
+        config.urlCache = nil
+        config.requestCachePolicy = .reloadIgnoringLocalAndRemoteCacheData
+        return URLSession(configuration: config)
+    }()
+
     public func downloadData(
         from url: URL,
         followRedirects: Bool,
         authHeader: String?,
         completion: @escaping @Sendable (Data?, Error?) -> Void
     ) {
-        var request = URLRequest(url: url)
+        var request = URLRequest(url: url, cachePolicy: .reloadIgnoringLocalAndRemoteCacheData)
         if let header = authHeader {
             request.addValue(header, forHTTPHeaderField: "Authorization")
         }
-        let session = URLSession(configuration: .default)
-        session.dataTask(with: request) { data, _, error in
+        Self.noCacheSession.dataTask(with: request) { data, _, error in
             completion(data, error)
         }.resume()
     }
@@ -39,16 +51,16 @@ public final class NetworkManager {
             completion(.failure(DownloadError.invalidURL))
             return
         }
-        var request = URLRequest(url: url)
+        var request = URLRequest(url: url, cachePolicy: .reloadIgnoringLocalAndRemoteCacheData)
         if let header = authHeader ?? authorizationHeader {
             request.addValue(header, forHTTPHeaderField: "Authorization")
         }
 
-        let session = URLSession(configuration: .default)
-
-        // Use dataTask instead of downloadTask to avoid system temp directory
-        // which is read-only during Setup Assistant
-        let task = session.dataTask(with: request) { data, _, error in
+        // Use dataTask instead of downloadTask to avoid the system temp directory,
+        // which is read-only during Setup Assistant. Route through the shared
+        // no-cache session so manifest and artifact bytes always reflect origin
+        // truth (a stale cached payload would defeat the per-item hash check).
+        let task = Self.noCacheSession.dataTask(with: request) { data, _, error in
             if let error = error {
                 completion(.failure(error))
                 return