ζ-1 abgeschlossen: DeepLinkRouter + Web-Header-Hide

- DeepLinkRouter als pure-Logic-Enum aus RootView extrahiert
  (resolveToWebURL, isExplorePath, route)
- 11 DeepLinkRouterTests grün: custom-scheme, https passthrough,
  Erkunden-vs-Lesen-Routing, Substring-Guard
- WebShellScripts.hideWebHeader: WKUserScript injiziert at
  document.start CSS, das den zitare-Web-Header
  (body header:has(a.brand)) ausblendet. Native TabBar
  übernimmt globale Navigation, Content bleibt sichtbar.
- Simulator-Verifikation: Quote rendert ohne doppelte Nav-Leiste,
  17 (UI + Unit) Tests grün

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

Sources/App/RootView.swift

@@ -71,46 +71,16 @@ struct RootView: View {
     /// `https://zitare.com/q/<slug>` umgemappt.
     private func handle(url: URL) {
         Log.app.info("Deep-Link empfangen: \(url.absoluteString, privacy: .public)")
-
-        let resolved = resolveToWebURL(url)
-        let path = resolved.path
+        let routed = DeepLinkRouter.route(url, base: AppConfig.webBaseURL)
         reloadCounter += 1
-
-        if isExplorePath(path) {
-            exploreTarget = WebTarget(url: resolved, reloadToken: reloadCounter)
+        if routed.isExplore {
+            exploreTarget = WebTarget(url: routed.url, reloadToken: reloadCounter)
             selectedTab = .explore
         } else {
-            readTarget = WebTarget(url: resolved, reloadToken: reloadCounter)
+            readTarget = WebTarget(url: routed.url, reloadToken: reloadCounter)
             selectedTab = .read
         }
     }
-
-    /// `zitare://quote/spitteler-...` → `https://zitare.com/q/spitteler-...`.
-    /// `zitare://author/x` → `https://zitare.com/a/x`.
-    /// `zitare://collection/x` → `https://zitare.com/c/x`.
-    /// `https://zitare.com/<anything>` bleibt wie es ist.
-    private func resolveToWebURL(_ url: URL) -> URL {
-        if url.scheme == "zitare" {
-            let host = url.host ?? ""
-            let path = url.path
-            switch host {
-            case "quote":
-                return AppConfig.webBaseURL.appendingPathComponent("q\(path)")
-            case "author":
-                return AppConfig.webBaseURL.appendingPathComponent("a\(path)")
-            case "collection":
-                return AppConfig.webBaseURL.appendingPathComponent("c\(path)")
-            default:
-                return AppConfig.webBaseURL
-            }
-        }
-        return url
-    }
-
-    private func isExplorePath(_ path: String) -> Bool {
-        let prefixes = ["/explore", "/region", "/thema", "/rolle", "/epoche", "/sprache", "/search", "/t/"]
-        return prefixes.contains { path == $0 || path.hasPrefix($0 + "/") }
-    }
 }
 
 enum AppTab: Hashable {