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/DeepLinkRouter.swift

@@ -0,0 +1,38 @@
+import Foundation
+
+/// Routet sowohl Custom-Scheme- (`zitare://`) als auch Universal-Link-URLs
+/// (`zitare.com/...`) auf eine konkrete `WebTarget` + Ziel-Tab.
+///
+/// Pure-Logic, kein State — easy testbar.
+enum DeepLinkRouter {
+    /// Mapt eine externe URL auf eine WebShell-URL.
+    /// `zitare://quote/x` → `https://zitare.com/q/x`,
+    /// `zitare://author/x` → `https://zitare.com/a/x`,
+    /// `zitare://collection/x` → `https://zitare.com/c/x`.
+    /// `https://*` bleibt unverändert.
+    static func resolveToWebURL(_ url: URL, base: URL) -> URL {
+        if url.scheme == "zitare" {
+            let host = url.host ?? ""
+            let path = url.path
+            switch host {
+            case "quote": return base.appendingPathComponent("q\(path)")
+            case "author": return base.appendingPathComponent("a\(path)")
+            case "collection": return base.appendingPathComponent("c\(path)")
+            default: return base
+            }
+        }
+        return url
+    }
+
+    /// `true` wenn der Pfad in den Erkunden-Tab gehört. Sonst Lesen-Tab.
+    static func isExplorePath(_ path: String) -> Bool {
+        let prefixes = ["/explore", "/region", "/thema", "/rolle", "/epoche", "/sprache", "/search", "/t/"]
+        return prefixes.contains { path == $0 || path.hasPrefix($0 + "/") }
+    }
+
+    /// One-Shot-Resolution: URL + Base → (resolvedURL, isExploreTab).
+    static func route(_ url: URL, base: URL) -> (url: URL, isExplore: Bool) {
+        let resolved = resolveToWebURL(url, base: base)
+        return (resolved, isExplorePath(resolved.path))
+    }
+}

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 {

Sources/Features/WebShell/WebShellScripts.swift

@@ -0,0 +1,30 @@
+import Foundation
+import WebKit
+
+/// User-Scripts, die in jeden `WKWebView` injiziert werden.
+///
+/// `WKUserScript` ist MainActor-isolated; deshalb sind die Factory-
+/// Methoden hier ebenfalls MainActor. Aufrufer leben sowieso auf Main
+/// (SwiftUI `makeUIView`/`makeNSView` sind MainActor).
+@MainActor
+enum WebShellScripts {
+    /// Versteckt den zitare-Web-Header (`<header>` mit `<a class="brand">`),
+    /// weil die native TabBar bereits global navigiert. Footer und
+    /// Hauptinhalt bleiben sichtbar.
+    ///
+    /// CSS wird at document.start als `<style>`-Tag injiziert — vor dem
+    /// First Paint, kein Flicker.
+    static let hideWebHeader: WKUserScript = .init(
+        source: """
+        (function() {
+            var css = 'body header:has(a.brand) { display: none !important; }';
+            var style = document.createElement('style');
+            style.setAttribute('data-zitare-native', 'hide-web-header');
+            style.textContent = css;
+            (document.head || document.documentElement).appendChild(style);
+        })();
+        """,
+        injectionTime: .atDocumentStart,
+        forMainFrameOnly: true
+    )
+}

Sources/Features/WebShell/WebShellView.swift

@@ -102,6 +102,7 @@ final class WebNavState {
             let config = WKWebViewConfiguration()
             config.websiteDataStore = .default()
             config.applicationNameForUserAgent = "ZitareNative/0.1 (iOS)"
+            config.userContentController.addUserScript(WebShellScripts.hideWebHeader)
             let webView = WKWebView(frame: .zero, configuration: config)
             webView.navigationDelegate = context.coordinator
             webView.uiDelegate = context.coordinator
@@ -149,6 +150,7 @@ final class WebNavState {
             let config = WKWebViewConfiguration()
             config.websiteDataStore = .default()
             config.applicationNameForUserAgent = "ZitareNative/0.1 (macOS)"
+            config.userContentController.addUserScript(WebShellScripts.hideWebHeader)
             let webView = WKWebView(frame: .zero, configuration: config)
             webView.navigationDelegate = context.coordinator
             webView.uiDelegate = context.coordinator