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/prompt-agent.md

@@ -19,5 +19,5 @@ Eino Chain 驱动的智能提示词生成
 </v-clicks>
 
 <div class="flex justify-center mt-2">
-  <img src="../public/prompt-agent.svg" class="w-full max-h-[140px] object-contain" />
+  <img src="../public/prompt-agent.svg" class="w-full max-h-[160px] object-contain" />
 </div>