```

feat(iOS): 更新MNN后端模型配置优化性能

将MNN主模型从Qwen3.5-4B(~2.64GiB)降级为Qwen3.5-2B(~1.1GiB)，因为4B版本
实测运行过慢，影响用户体验。iPhone17+/SME2设备使用2B模型，保留MLX
兜底方案用于模拟器和备用场景，确保AI推理性能和存储效率的平衡。
```

康康/Features/Diary/DiaryQuickSheet.swift

@@ -182,6 +182,7 @@ struct DiaryQuickSheet: View {
                         questionRow(index: roundLocalIndex(at: idx), question: q)
                     }
                 }
+                AIDisclaimerFooter()
             }
 
             if exhaustedNote {
@@ -212,30 +213,12 @@ struct DiaryQuickSheet: View {
                     ? String(appLoc: "让 AI 帮我想想还能记什么")
                     : String(appLoc: "先写几个字,AI 来帮忙补充"),
                 enabled: canRequestSuggest,
+                prominent: true,
                 action: requestSuggestions
             )
 
         case .loading:
-            HStack(spacing: 10) {
-                ProgressView().controlSize(.small)
-                Text("AI 思考中…  本地推理,通常 5-10 秒")
-                    .font(.tjScaled( 13))
-                    .foregroundStyle(Tj.Palette.text2)
-                Spacer()
-                Button("取消") { cancelSuggestions() }
-                    .font(.tjScaled( 12, weight: .semibold))
-                    .foregroundStyle(Tj.Palette.text3)
-            }
-            .padding(.vertical, 11)
-            .padding(.horizontal, 12)
-            .background(
-                RoundedRectangle(cornerRadius: Tj.Radius.sm, style: .continuous)
-                    .fill(Tj.Palette.paper)
-            )
-            .overlay(
-                RoundedRectangle(cornerRadius: Tj.Radius.sm, style: .continuous)
-                    .strokeBorder(Tj.Palette.lineSoft, lineWidth: 1)
-            )
+            assistLoadingIndicator
 
         case .ready:
             assistPrimaryButton(
@@ -273,26 +256,25 @@ struct DiaryQuickSheet: View {
         }
     }
 
+    /// 辅助主按钮。`prominent` 为真走实心强调样式(填充 brick + 白字 + 轻投影,一眼可点),
+    /// 否则走低调描边样式(用于 .ready 的「再问一轮」)。
     private func assistPrimaryButton(icon: String,
                                      label: String,
                                      enabled: Bool,
+                                     prominent: Bool = false,
                                      action: @escaping () -> Void) -> some View {
         Button(action: action) {
             HStack(spacing: 8) {
                 Image(systemName: icon)
                 Text(label)
             }
-            .font(.tjScaled( 13, weight: .semibold))
-            .foregroundStyle(enabled ? Tj.Palette.ink : Tj.Palette.text3)
+            .font(.tjScaled( prominent ? 14 : 13, weight: .semibold))
+            .foregroundStyle(prominent
+                ? (enabled ? Tj.Palette.paper : Tj.Palette.text3)
+                : (enabled ? Tj.Palette.ink : Tj.Palette.text3))
             .frame(maxWidth: .infinity)
-            .padding(.vertical, 11)
-            .background(
-                RoundedRectangle(cornerRadius: Tj.Radius.sm, style: .continuous)
-                    .strokeBorder(
-                        enabled ? Tj.Palette.ink : Tj.Palette.line,
-                        style: StrokeStyle(lineWidth: 1, dash: enabled ? [] : [3, 3])
-                    )
-            )
+            .padding(.vertical, prominent ? 14 : 11)
+            .background(assistButtonBackground(enabled: enabled, prominent: prominent))
             // 纯描边背景、内部透明:补 contentShape 让整框可点(否则只有图标+文字本体能点)。
             .contentShape(Rectangle())
         }
@@ -300,6 +282,58 @@ struct DiaryQuickSheet: View {
         .disabled(!enabled)
     }
 
+    @ViewBuilder
+    private func assistButtonBackground(enabled: Bool, prominent: Bool) -> some View {
+        let shape = RoundedRectangle(cornerRadius: Tj.Radius.sm, style: .continuous)
+        if prominent {
+            shape
+                .fill(enabled ? Tj.Palette.brick : Tj.Palette.brickSoft)
+                .shadow(color: enabled ? Tj.Palette.brick.opacity(0.30) : .clear,
+                        radius: 8, x: 0, y: 3)
+        } else {
+            shape
+                .strokeBorder(
+                    enabled ? Tj.Palette.ink : Tj.Palette.line,
+                    style: StrokeStyle(lineWidth: 1, dash: enabled ? [] : [3, 3])
+                )
+        }
+    }
+
+    /// .loading 等待态:安静的 paper 卡片,底部一条细窄的不确定进度条来回滑动(Linear/Vercel 式极简)。
+    /// 不用高亮扫光、不填强调色,避免刺眼;只靠细线 + sparkles 轻脉冲传达「在算」。
+    private var assistLoadingIndicator: some View {
+        HStack(spacing: 10) {
+            Image(systemName: "sparkles")
+                .font(.tjScaled( 12, weight: .semibold))
+                .foregroundStyle(Tj.Palette.brick)
+                .symbolEffect(.pulse, options: .repeating)
+            Text(lastRate > 0
+                 ? String(format: String(appLoc: "AI 生成中 · %.1f tok/s"), lastRate)
+                 : String(appLoc: "AI 生成中 · 本地推理"))
+                .font(.tjScaled( 13, weight: .medium))
+                .foregroundStyle(Tj.Palette.text2)
+            Spacer(minLength: 0)
+            Button("取消") { cancelSuggestions() }
+                .font(.tjScaled( 12, weight: .semibold))
+                .foregroundStyle(Tj.Palette.text3)
+        }
+        .padding(.vertical, 11)
+        .padding(.horizontal, 12)
+        .frame(maxWidth: .infinity)
+        .background(
+            RoundedRectangle(cornerRadius: Tj.Radius.sm, style: .continuous)
+                .fill(Tj.Palette.paper)
+        )
+        .overlay(
+            RoundedRectangle(cornerRadius: Tj.Radius.sm, style: .continuous)
+                .strokeBorder(Tj.Palette.lineSoft, lineWidth: 1)
+        )
+        .overlay(alignment: .bottom) {
+            AIFlowBar().padding(.horizontal, 1)
+        }
+        .clipShape(RoundedRectangle(cornerRadius: Tj.Radius.sm, style: .continuous))
+    }
+
     /// 给定整张 questions list 里 idx 位置的 question,返回它在自己 round 内的序号(1-based)。
     private func roundLocalIndex(at idx: Int) -> Int {
         let target = questions[idx].round