test(overview): the matrix gains a ninth row for Qwen3.8-Flash-Next

Adding a default model adds a matrix row, and the AgentX-only curation makes
it exactly one. MATRIX_ROWS moves 8 -> 9, which is what CI reported against the
overview fixtures.

中文：新增 default 模型会为 overview 矩阵增加一行，而仅 AgentX 的策展使其恰好为一行。
MATRIX_ROWS 由 8 改为 9，与 CI 基于 overview fixture 的实际结果一致。

Author: functionstackx

packages/app/cypress/e2e/overview.cy.ts

@@ -21,8 +21,9 @@ const PLATFORM_HEADERS = [
 ];
 
 const SINGLE_TURN = 'single_turn_8k1k';
-/** Five models, three of them with both a single-turn and an AgentX row. */
-const MATRIX_ROWS = 8;
+/** Six models: three with both a single-turn and an AgentX row, and three
+ *  curated AgentX-only (Kimi K3, GLM 5.2, Qwen3.8-Flash-Next). */
+const MATRIX_ROWS = 9;
 const AGENTX = 'agentx';
 const AGENTX_LABEL = 'Long Context Multi-Turn Realistic Agentic Scenario (AgentX)';
 const AGENTX_LABEL_ZH = '长上下文、多轮交互的真实智能体场景（AgentX）';