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/opencode/test/cli/run/footer.width.test.ts

@@ -0,0 +1,35 @@
+import { describe, expect, test } from "bun:test"
+import { footerWidthPolicy } from "@/cli/cmd/run/footer.width"
+
+describe("run footer width", () => {
+  test("preserves shared dialog and statusline breakpoints", () => {
+    const narrow = footerWidthPolicy(79)
+    expect(narrow.dialog.narrow).toBe(true)
+    expect(narrow.statusline.showActivityMeta).toBe(false)
+    expect(narrow.statusline.showCommandHint).toBe(true)
+    expect(narrow.statusline.showContextHints).toBe(false)
+    expect(narrow.statusline.contextHintLimit).toBe(0)
+    expect(narrow.statusline.showModel).toBe(false)
+
+    const command = footerWidthPolicy(65)
+    expect(command.statusline.showCommandHint).toBe(false)
+
+    const commandHint = footerWidthPolicy(66)
+    expect(commandHint.statusline.showCommandHint).toBe(true)
+
+    const compact = footerWidthPolicy(80)
+    expect(compact.dialog.narrow).toBe(false)
+    expect(compact.statusline.showActivityMeta).toBe(true)
+    expect(compact.statusline.showContextHints).toBe(true)
+    expect(compact.statusline.contextHintLimit).toBe(1)
+    expect(compact.statusline.showModel).toBe(false)
+
+    const model = footerWidthPolicy(120)
+    expect(model.statusline.contextHintLimit).toBe(2)
+    expect(model.statusline.showModel).toBe(true)
+
+    const spacious = footerWidthPolicy(150)
+    expect(spacious.statusline.contextHintLimit).toBeUndefined()
+    expect(spacious.statusline.showModel).toBe(true)
+  })
+})