feat: 品牌替换 + 启动优化 + AGENTS.md 模板定制

- 品牌替换：OpenCode/opencode → AirCoding/aircoding（16+ 文件）
- Logo ASCII art：修复 left/right 行数不匹配导致的启动崩溃
- 启动诊断：添加 OPENCODE_PRINT_TIMING 计时探针
- dev 模式默认 --pure 跳过外部插件加载
- AGENTS.md 模板：追加 AirCoding 多 Agent 专项段落
- architect prompt + plugin：强化 AGENTS.md 产出验证

packages/core/migration/20260410174513_workspace-name/migration.sql

@@ -0,0 +1,16 @@
+PRAGMA foreign_keys=OFF;--> statement-breakpoint
+CREATE TABLE `__new_workspace` (
+	`id` text PRIMARY KEY,
+	`type` text NOT NULL,
+	`name` text DEFAULT '' NOT NULL,
+	`branch` text,
+	`directory` text,
+	`extra` text,
+	`project_id` text NOT NULL,
+	CONSTRAINT `fk_workspace_project_id_project_id_fk` FOREIGN KEY (`project_id`) REFERENCES `project`(`id`) ON DELETE CASCADE
+);
+--> statement-breakpoint
+INSERT INTO `__new_workspace`(`id`, `type`, `branch`, `name`, `directory`, `extra`, `project_id`) SELECT `id`, `type`, `branch`, `name`, `directory`, `extra`, `project_id` FROM `workspace`;--> statement-breakpoint
+DROP TABLE `workspace`;--> statement-breakpoint
+ALTER TABLE `__new_workspace` RENAME TO `workspace`;--> statement-breakpoint
+PRAGMA foreign_keys=ON;