Ban Yaro Go — Phase 1 Foundation

SwiftUI/SwiftData iOS-Client, redet mit https://banyaro.app FastAPI-Backend.
Bundle-ID app.banyaro.ios, Xcode-26-Projekt mit synchronisierten Ordnern.

Drin:
- APIClient (URLSession + Bearer + convertFromSnakeCase Decoder)
- KeychainStore + AuthSession (@Observable) für persistenten Login
- LoginView, MainTabView, SettingsView (mit Logout)
- RoutesListView + RouteDetailView mit MapKit-Polyline aus preview_track
- DogsListView mit Foto-Avatar
- App-Icon (Pfote auf Banyaro-Amber)

BanYaroGo/API/APIClient.swift

@@ -0,0 +1,67 @@
+import Foundation
+
+final class APIClient {
+    static let shared = APIClient()
+
+    let baseURL = URL(string: "https://banyaro.app")!
+    var token: String?
+
+    private let session: URLSession = .shared
+    private let decoder: JSONDecoder = {
+        let d = JSONDecoder()
+        d.keyDecodingStrategy = .convertFromSnakeCase
+        return d
+    }()
+    private let encoder: JSONEncoder = {
+        let e = JSONEncoder()
+        return e
+    }()
+
+    func get<T: Decodable>(_ path: String) async throws -> T {
+        try await perform(method: "GET", path: path, body: nil)
+    }
+
+    func post<T: Decodable, B: Encodable>(_ path: String, body: B) async throws -> T {
+        let data = try encoder.encode(body)
+        return try await perform(method: "POST", path: path, body: data)
+    }
+
+    func post<T: Decodable>(_ path: String) async throws -> T {
+        try await perform(method: "POST", path: path, body: nil)
+    }
+
+    private func perform<T: Decodable>(method: String, path: String, body: Data?) async throws -> T {
+        let url = baseURL.appending(path: path)
+        var req = URLRequest(url: url)
+        req.httpMethod = method
+        req.setValue("application/json", forHTTPHeaderField: "Accept")
+        if let token {
+            req.setValue("Bearer \(token)", forHTTPHeaderField: "Authorization")
+        }
+        if let body {
+            req.setValue("application/json", forHTTPHeaderField: "Content-Type")
+            req.httpBody = body
+        }
+
+        let (data, response) = try await session.data(for: req)
+        guard let http = response as? HTTPURLResponse else {
+            throw APIError.invalidResponse
+        }
+        guard (200..<300).contains(http.statusCode) else {
+            let detail = Self.parseErrorDetail(from: data)
+            throw APIError.server(status: http.statusCode, message: detail)
+        }
+        return try decoder.decode(T.self, from: data)
+    }
+
+    /// FastAPI returns errors as {"detail": "message"} or {"detail": [{...}]}.
+    private static func parseErrorDetail(from data: Data) -> String? {
+        if let obj = try? JSONSerialization.jsonObject(with: data) as? [String: Any] {
+            if let s = obj["detail"] as? String { return s }
+            if let arr = obj["detail"] as? [[String: Any]],
+               let first = arr.first,
+               let msg = first["msg"] as? String { return msg }
+        }
+        return nil
+    }
+}