Modernize networking layer and fix category navigation and recipe list bugs

Network layer:
- Replace static CookbookApi protocol with instance-based CookbookApiProtocol
  using async/throws instead of tuple returns
- Refactor ApiRequest to use URLComponents for proper URL encoding, replace
  print statements with OSLog, and return typed NetworkError cases
- Add structured NetworkError variants (httpError, connectionError, etc.)
- Remove global cookbookApi constant in favor of injected dependency on AppState
- Delete unused RecipeEditViewModel, RecipeScraper, and Scraper playground

Data & model fixes:
- Add custom Decodable for RecipeDetail with safe fallbacks for malformed JSON
- Make Category Hashable/Equatable use only `name` so NavigationSplitView
  selection survives category refreshes with updated recipe_count
- Return server-assigned ID from uploadRecipe so new recipes get their ID
  before the post-upload refresh block executes

View updates:
- Refresh both old and new category recipe lists after upload when category
  changes, mapping empty recipeCategory to "*" for uncategorized recipes
- Raise deployment target to iOS 18, adopt new SwiftUI API conventions
- Clean up alerts, onboarding views, and settings

Co-Authored-By: Claude Sonnet 4.5 <noreply@anthropic.com>

Nextcloud Cookbook iOS Client/Data/DataStore.swift

@@ -6,12 +6,13 @@
 //
 
 import Foundation
+import OSLog
 import SwiftUI
 
 class DataStore {
     let fileManager = FileManager.default
     static let shared = DataStore()
-    
+
     private static func fileURL(appending: String) throws -> URL {
         try FileManager.default.url(
             for: .documentDirectory,
@@ -21,7 +22,7 @@ class DataStore {
         )
         .appendingPathComponent(appending)
     }
-    
+
     private static func fileURL() throws -> URL {
         try FileManager.default.url(
             for: .documentDirectory,
@@ -30,7 +31,7 @@ class DataStore {
             create: false
         )
     }
-    
+
     func load<D: Decodable>(fromPath path: String) async throws -> D? {
         let task = Task<D?, Error> {
             let fileURL = try Self.fileURL(appending: path)
@@ -42,7 +43,7 @@ class DataStore {
         }
         return try await task.value
     }
-    
+
     func save<D: Encodable>(data: D, toPath path: String) async {
         let task = Task {
             let data = try JSONEncoder().encode(data)
@@ -52,42 +53,36 @@ class DataStore {
         do {
             _ = try await task.value
         } catch {
-            print("Could not save data (path: \(path)")
+            Logger.data.error("Could not save data (path: \(path))")
         }
     }
-    
+
     func delete(path: String) {
         Task {
             let fileURL = try Self.fileURL(appending: path)
             try fileManager.removeItem(at: fileURL)
         }
     }
-    
+
     func recipeDetailExists(recipeId: Int) -> Bool {
         let filePath = "recipe\(recipeId).data"
         guard let folderPath = fileManager.urls(for: .documentDirectory, in: .userDomainMask).first?.path() else { return false }
         return fileManager.fileExists(atPath: folderPath + filePath)
     }
-    
+
     func clearAll() -> Bool {
-        print("Attempting to delete all data ...")
+        Logger.data.debug("Attempting to delete all data ...")
         guard let folderPath = fileManager.urls(for: .documentDirectory, in: .userDomainMask).first?.path() else { return false }
-        print("Folder path: ", folderPath)
         do {
             let filePaths = try fileManager.contentsOfDirectory(atPath: folderPath)
             for filePath in filePaths {
-                print("File path: ", filePath)
                 try fileManager.removeItem(atPath: folderPath + filePath)
             }
         } catch {
-            print("Could not delete documents folder contents: \(error)")
+            Logger.data.error("Could not delete documents folder contents: \(error.localizedDescription)")
             return false
         }
-        print("Done.")
+        Logger.data.debug("All data deleted successfully.")
         return true
-        
     }
 }
-
-
-