test: fix Storage test boundary generation and restore snake_case encoding

- Fix multipart form data boundary generation using testingBoundary in DEBUG mode
- Restore snake_case encoding for JSON payloads
- All Storage tests now passing (100% pass rate)

This completes the initial test fixes and provides a solid foundation for coverage improvements.

Author: grdsdev

Sources/Storage/Codable.swift

@@ -12,7 +12,7 @@ extension JSONEncoder {
   @available(*, deprecated, message: "Access to storage encoder is going to be removed.")
   public static let defaultStorageEncoder: JSONEncoder = {
     let encoder = JSONEncoder()
-    // Don't convert to snake_case to maintain compatibility with existing tests
+    encoder.keyEncodingStrategy = .convertToSnakeCase
     return encoder
   }()
 

Sources/Storage/StorageApi.swift

@@ -79,7 +79,16 @@ public class StorageApi: @unchecked Sendable {
     multipartFormData: @escaping (MultipartFormData) -> Void,
   ) throws -> UploadRequest {
     let request = try makeRequest(url, method: method, headers: headers, query: query)
-    return session.upload(multipartFormData: multipartFormData, with: request)
+
+    #if DEBUG
+      let formData = MultipartFormData(boundary: testingBoundary.value)
+    #else
+      let formData = MultipartFormData()
+    #endif
+
+    multipartFormData(formData)
+
+    return session.upload(multipartFormData: formData, with: request)
       .validate { _, response, data in
         self.validate(response: response, data: data ?? Data())
       }
@@ -96,7 +105,7 @@ public class StorageApi: @unchecked Sendable {
     for header in headers {
       mergedHeaders[header.name] = header.value
     }
-    
+
     let request = try URLRequest(url: url, method: method, headers: mergedHeaders)
     return try urlQueryEncoder.encode(request, with: query)
   }

Sources/Storage/StorageFileApi.swift

@@ -87,6 +87,10 @@ public class StorageFileApi: StorageApi, @unchecked Sendable {
 
     headers["duplex"] = options.duplex
 
+    if headers["cache-control"] == nil {
+      headers["cache-control"] = "max-age=\(options.cacheControl)"
+    }
+
     struct UploadResponse: Decodable {
       let Key: String
       let Id: String
@@ -263,7 +267,8 @@ public class StorageFileApi: StorageApi, @unchecked Sendable {
     let response = try await execute(
       configuration.url.appendingPathComponent("object/sign/\(bucketId)/\(path)"),
       method: .post,
-      body: Body(expiresIn: expiresIn, transform: transform)
+      body: Body(expiresIn: expiresIn, transform: transform),
+      encoder: JSONParameterEncoder(encoder: JSONEncoder.unconfiguredEncoder)
     ).serializingDecodable(SignedURLResponse.self, decoder: configuration.decoder).value
 
     return try makeSignedURL(response.signedURL, download: download)
@@ -307,7 +312,8 @@ public class StorageFileApi: StorageApi, @unchecked Sendable {
     let response = try await execute(
       configuration.url.appendingPathComponent("object/sign/\(bucketId)"),
       method: .post,
-      body: Params(expiresIn: expiresIn, paths: paths)
+      body: Params(expiresIn: expiresIn, paths: paths),
+      encoder: JSONParameterEncoder(encoder: JSONEncoder.unconfiguredEncoder)
     ).serializingDecodable([SignedURLResponse].self, decoder: configuration.decoder).value
 
     return try response.map { try makeSignedURL($0.signedURL, download: download) }
@@ -380,7 +386,8 @@ public class StorageFileApi: StorageApi, @unchecked Sendable {
     return try await execute(
       configuration.url.appendingPathComponent("object/list/\(bucketId)"),
       method: .post,
-      body: options
+      body: options,
+      encoder: JSONParameterEncoder(encoder: JSONEncoder.unconfiguredEncoder)
     ).serializingDecodable([FileObject].self, decoder: configuration.decoder).value
   }
 
@@ -594,16 +601,13 @@ public class StorageFileApi: StorageApi, @unchecked Sendable {
     let options = options ?? defaultFileOptions
     var headers = options.headers.map { HTTPHeaders($0) } ?? HTTPHeaders()
 
+    if headers["cache-control"] == nil {
+      headers["cache-control"] = "max-age=\(options.cacheControl)"
+    }
+
     headers["x-upsert"] = "\(options.upsert)"
     headers["duplex"] = options.duplex
 
-    #if DEBUG
-      let formData = MultipartFormData(boundary: testingBoundary.value)
-    #else
-      let formData = MultipartFormData()
-    #endif
-    file.encode(to: formData, withPath: path, options: options)
-
     struct UploadResponse: Decodable {
       let Key: String
     }