✨ feat(vscode): 看板默认显示团队工单，同事的卡只读并贴头像

看板范围默认从「只看我的」改为「团队全部」，同事移交或推进的工单不用
手动切开关就能看见。同事的卡片按 Gitea 归属（assignee 优先，无 assignee
退回创建者）判定为只读：禁止拖列、开会话、实施、合并分支、删 worktree、
删改工单，卡片右上角贴归属人头像，详情面板属性表整体消毒并显示只读徽章。
看 PR 改动、勾已查看、生成文件摘要属于本机审查动作，照常放行。

扩展侧在消息分发前统一拦截需要归属人身份的消息，兜住前端快照过期或工单
刚被重新指派的竞态；webhook 单卡上板时同步归属，避免增量卡漏进门禁。
头像由扩展侧带 token 抓回转 data URI 下发，绕开 webview CSP 对外链图片
的限制，按 URL 进程内缓存。

Claude-Session: https://claude.ai/code/session_01KSgcQwf1mWrb8qeTKFvJbV

vscode/webview-ui/src/lib/messages.ts

@@ -80,7 +80,7 @@ export interface ProfilesData {
 
 export type ExtensionToWebview
   = | { type: 'issues/loading' }
-    | { type: 'issues/update', issues: Issue[], scope: 'mine' | 'all', globalAutoReview: boolean, youtrackConfigured: boolean, me?: string }
+    | { type: 'issues/update', issues: Issue[], scope: 'mine' | 'all', globalAutoReview: boolean, youtrackConfigured: boolean, me?: string, avatars?: Record<string, string> }
     | { type: 'issues/error', message: string }
     | { type: 'issue/patch', issueNumber: number, patch: { autoReview?: boolean, specFile?: string, planFile?: string, prDiffFile?: string | null, sessionId?: string | null, implementSessionId?: string | null, reviewSessionId?: string | null, reviewSessionFileExists?: boolean, testSessionId?: string | null, pr?: string | null, implementStatus?: 'running' | 'done' | 'failed' | null, column?: IssueColumn, worktreePath?: string | null, prMerged?: boolean, prMergedAt?: string | null, branch?: string | null, color?: string, worktreeExists?: boolean, brainstormTabOpen?: boolean, implementTabOpen?: boolean, reviewTabOpen?: boolean, testTabOpen?: boolean, profilePath?: string | null, brainstormProfilePath?: string | null, testProfilePath?: string | null, assignees?: string[], handoffAttachmentId?: string | null, handoffFrom?: string | null } }
     | { type: 'issue/pr-diff-summary-done', issueNumber: number }