style: optimize gen2D deck layout, animations, and visual hierarchy

- style-keys.md: add v-clicks to 3x2 grid for staggered animation
- eino-graph.md: two-column layout (code left, Items right)
- eino-deep-dive.md: two-column layout for both slides, code+Items side-by-side
- async-deep-dive.md: two-column layout for both slides, SVG integrated
- harness.md: two-column layout for slide 1 (code left, Items right)
- request-journey.md: two-column layout for journey steps
- data-model.md: add v-clicks to grid items, increase diagram height
- architecture/pipeline/prompt-agent: increase SVG max-height for better visibility

decks/gen2D/pages/async-deep-dive.md

@@ -2,7 +2,9 @@
 
 FIFO 串行执行，信号驱动调度
 
-<div class="mt-2">
+<div class="grid grid-cols-2 gap-4 mt-2">
+
+<div>
 
 ```go {1-6|8-12|all}
 type TaskQueue struct {
@@ -22,6 +24,8 @@ func (q *TaskQueue) Enqueue(job *TaskJob) {
 
 </div>
 
+<div class="flex flex-col justify-center">
+
 <v-clicks>
 
 <Item title="Enqueue → run() → processNext() 流程">
@@ -34,13 +38,19 @@ func (q *TaskQueue) Enqueue(job *TaskJob) {
 
 </v-clicks>
 
+</div>
+
+</div>
+
 ---
 
 # 进度推送与 WebSocket
 
 Context 注入 + 多通道推送
 
-<div class="mt-2">
+<div class="grid grid-cols-2 gap-4 mt-2">
+
+<div>
 
 ```go {1-3|5-8|all}
 func WithProgressReporter(ctx context.Context, r ProgressReporter) context.Context {
@@ -52,8 +62,14 @@ reporter := GetProgressReporter(ctx)
 reporter.Report(Progress{Stage: "prompt", Percent: 25})
 ```
 
+<div class="flex justify-center mt-2">
+  <img src="../public/async-task.svg" class="w-full max-h-[160px] object-contain" />
 </div>
 
+</div>
+
+<div class="flex flex-col justify-center">
+
 <v-clicks>
 
 <Item title="进度阶段划分">
@@ -66,6 +82,6 @@ reporter.Report(Progress{Stage: "prompt", Percent: 25})
 
 </v-clicks>
 
-<div class="flex justify-center mt-2">
-  <img src="../public/async-task.svg" class="w-full max-h-[180px] object-contain" />
+</div>
+
 </div>