Remove Codestral provider

Author: Agent! for MacOS

Sources/AgentTools/APIProvider.swift

@@ -7,7 +7,6 @@ public enum APIProvider: String, CaseIterable, Codable, Sendable {
     case gemini = "gemini"
     case grok = "grok"
     case mistral = "mistral"
-    case codestral = "codestral"
     case vibe = "vibe"
     case deepSeek = "deepSeek"
     case huggingFace = "huggingFace"
@@ -30,7 +29,6 @@ public enum APIProvider: String, CaseIterable, Codable, Sendable {
         case .gemini: "Google Gemini"
         case .grok: "Grok"
         case .mistral: "Mistral"
-        case .codestral: "Codestral"
         case .vibe: "Mistral Vibe"
         case .deepSeek: "DeepSeek"
         case .huggingFace: "Hugging Face"