Improve LSP Install UX (#2101)

### Description

Implements an installing progress view for language servers from the
mason registry.

- Package managers have been reworked to return a list of 'steps' to
execute.
- Created a model for running steps and waiting for confirmation if
required before a step.
- Added UI that observes the running model for executed steps and
output, as well as errors.

### Related Issues

* #1997 

### Checklist

- [x] I read and understood the [contributing
guide](https://github.com/CodeEditApp/CodeEdit/blob/main/CONTRIBUTING.md)
as well as the [code of
conduct](https://github.com/CodeEditApp/CodeEdit/blob/main/CODE_OF_CONDUCT.md)
- [x] The issues this PR addresses are related to each other
- [x] My changes generate no new warnings
- [x] My code builds and runs on my machine
- [x] My changes are all related to the related issue above
- [x] I documented my code

### Screenshots

https://github.com/user-attachments/assets/6f0f8a62-1034-4c15-bebe-8d01fff0019e

Author: thecoolwinter

CodeEdit/Features/ActivityViewer/Notifications/TaskNotificationHandler.swift

@@ -132,6 +132,7 @@ final class TaskNotificationHandler: ObservableObject {
     ///   - toWorkspace: The workspace to restrict the task to. Defaults to `nil`, which is received by all workspaces.
     ///   - action: The action being taken on the task.
     ///   - model: The task contents.
+    @MainActor
     static func postTask(toWorkspace: URL? = nil, action: Action, model: TaskNotificationModel) {
         NotificationCenter.default.post(name: .taskNotification, object: nil, userInfo: [
             "id": model.id,

CodeEdit/Features/CodeEditUI/Views/ErrorDescriptionLabel.swift

@@ -0,0 +1,36 @@
+//
+//  ErrorDescriptionLabel.swift
+//  CodeEdit
+//
+//  Created by Khan Winter on 8/14/25.
+//
+
+import SwiftUI
+
+struct ErrorDescriptionLabel: View {
+    let error: Error
+
+    var body: some View {
+        VStack(alignment: .leading) {
+            if let error = error as? LocalizedError {
+                if let description = error.errorDescription {
+                    Text(description)
+                }
+
+                if let reason = error.failureReason {
+                    Text(reason)
+                }
+
+                if let recoverySuggestion = error.recoverySuggestion {
+                    Text(recoverySuggestion)
+                }
+            } else {
+                Text(error.localizedDescription)
+            }
+        }
+    }
+}
+
+#Preview {
+    ErrorDescriptionLabel(error: CancellationError())
+}

CodeEdit/Features/LSP/Registry/Errors/PackageManagerError.swift

@@ -0,0 +1,46 @@
+//
+//  PackageManagerError.swift
+//  CodeEdit
+//
+//  Created by Abe Malla on 5/12/25.
+//
+
+import Foundation
+
+enum PackageManagerError: Error, LocalizedError {
+    case unknown
+    case packageManagerNotInstalled
+    case initializationFailed(String)
+    case installationFailed(String)
+    case invalidConfiguration
+
+    var errorDescription: String? {
+        switch self {
+        case .unknown:
+            "Unknown error occurred"
+        case .packageManagerNotInstalled:
+            "The required package manager is not installed."
+        case .initializationFailed:
+            "Installation directory initialization failed."
+        case .installationFailed:
+            "Package installation failed."
+        case .invalidConfiguration:
+            "The package registry contained an invalid installation configuration."
+        }
+    }
+
+    var failureReason: String? {
+        switch self {
+        case .unknown:
+            nil
+        case .packageManagerNotInstalled:
+            nil
+        case .initializationFailed(let string):
+            string
+        case .installationFailed(let string):
+            string
+        case .invalidConfiguration:
+            nil
+        }
+    }
+}

CodeEdit/Features/LSP/Registry/Errors/RegistryManagerError.swift

@@ -0,0 +1,47 @@
+//
+//  RegistryManagerError.swift
+//  CodeEdit
+//
+//  Created by Abe Malla on 5/12/25.
+//
+
+import Foundation
+
+enum RegistryManagerError: Error, LocalizedError {
+    case installationRunning
+    case invalidResponse(statusCode: Int)
+    case downloadFailed(url: URL, error: Error)
+    case maxRetriesExceeded(url: URL, lastError: Error)
+    case writeFailed(error: Error)
+    case failedToSaveRegistryCache
+
+    var errorDescription: String? {
+        switch self {
+        case .installationRunning:
+            "A package is already being installed."
+        case .invalidResponse(let statusCode):
+            "Invalid response received: \(statusCode)"
+        case .downloadFailed(let url, _):
+            "Download for \(url) error."
+        case .maxRetriesExceeded(let url, _):
+            "Maximum retries exceeded for url: \(url)"
+        case .writeFailed:
+            "Failed to write to file."
+        case .failedToSaveRegistryCache:
+            "Failed to write to registry cache."
+        }
+    }
+
+    var failureReason: String? {
+        switch self {
+        case .installationRunning, .invalidResponse, .failedToSaveRegistryCache:
+            return nil
+        case .downloadFailed(_, let error), .maxRetriesExceeded(_, let error), .writeFailed(let error):
+            return if let error = error as? LocalizedError {
+                error.errorDescription
+            } else {
+                error.localizedDescription
+            }
+        }
+    }
+}

CodeEdit/Features/LSP/Registry/InstallationQueueManager.swift

@@ -50,4 +50,42 @@ enum InstallationMethod: Equatable {
             return nil
         }
     }
+
+    func packageManager(installPath: URL) -> PackageManagerProtocol? {
+        switch packageManagerType {
+        case .npm:
+            return NPMPackageManager(installationDirectory: installPath)
+        case .cargo:
+            return CargoPackageManager(installationDirectory: installPath)
+        case .pip:
+            return PipPackageManager(installationDirectory: installPath)
+        case .golang:
+            return GolangPackageManager(installationDirectory: installPath)
+        case .github, .sourceBuild:
+            return GithubPackageManager(installationDirectory: installPath)
+        case .nuget, .opam, .gem, .composer:
+            // TODO: IMPLEMENT OTHER PACKAGE MANAGERS
+            return nil
+        default:
+            return nil
+        }
+    }
+
+    var installerDescription: String {
+        guard let packageManagerType else { return "Unknown" }
+        switch packageManagerType {
+        case .npm, .cargo, .golang, .pip, .sourceBuild, .github:
+            return packageManagerType.userDescription
+        case .nuget, .opam, .gem, .composer:
+            return "(Unsupported) \(packageManagerType.userDescription)"
+        }
+    }
+
+    var packageDescription: String? {
+        guard let packageName else { return nil }
+        if let version {
+            return "\(packageName)@\(version)"
+        }
+        return packageName
+    }
 }