✨ Diagnostic Manager

首先定位编辑器的 Issue Navigator 和 Line Annotations 组件，然后跟踪它们当前如何接收诊断数据。围绕需求定义 DiagnosticManager 和 DiagnosticIssue，并按文件和可观察的变更对更新进行分组；完成的标准是两个组件都能使用 manager 作为共享的诊断源。

Description

Introduce a DiagnosticManager responsible for managing and publishing diagnostics (e.g., build errors, linter warnings, language server issues) grouped by file. This manager will serve as the single source of truth for diagnostics across the editor, and its contents will drive visual components such as the Issue Navigator and Line Annotations.

Requirements

• Create a DiagnosticManager class conforming to ObservableObject
• Store diagnostics as a flat list or grouped by file:

  @Published var issues: [DiagnosticIssue]
  

• Define a DiagnosticIssue model:

  struct DiagnosticIssue: Identifiable, Hashable {
      let id: UUID = UUID()
      let file: URL
      let line: Int
      let column: Int?
      let message: String
      let severity: Severity
      let source: String?
      let fixItSuggestion: String?
  
      enum Severity {
          case error, warning, info, live
      }
  }
  

• Add convenience accessors:

  var issuesByFile: [URL: [DiagnosticIssue]]
  func issues(for file: URL) -> [DiagnosticIssue]
  

• Add a way to update issues by file, e.g.:

  func setIssues(_ issues: [DiagnosticIssue], for file: URL)
  func clearIssues(for file: URL)
  

Additional Context

This manager will be used by multiple parts of the app, including the Issue Navigator and Line Annotations. It should be reactive and efficient, allowing UI components to automatically update when diagnostics change.

Future extensions may include filtering, debouncing updates, or supporting different diagnostics sources (build system, LSP, etc.).

Related Issues

• #354
• #2015
• https://github.com/CodeEditApp/CodeEditSourceEditor/issues/297