Enhance Step3Simulation and Step2EnvSetup components for improved clarity and user experience

- Updated estimated time messages in Step2EnvSetup.vue to specify agent scale for better context.
- Refactored Step3Simulation.vue to improve action tracking, including clearer labels and enhanced UI elements.
- Introduced a tooltip for available actions, providing users with quick reference during simulations.
- Improved styling and layout for better readability and interaction, including adjustments to button and card designs.

frontend/src/components/Step2EnvSetup.vue

@@ -457,7 +457,7 @@
                     <span class="val-unit">轮</span>
                   </div>
                   <div class="slider-meta-info">
-                    <span>预计耗时约 {{ Math.round(customMaxRounds * 0.6) }} 分钟</span>
+                    <span>若Agent规模为100：预计耗时约 {{ Math.round(customMaxRounds * 0.6) }} 分钟</span>
                   </div>
                 </div>
 
@@ -497,7 +497,7 @@
                           <circle cx="12" cy="12" r="10"></circle>
                           <polyline points="12 6 12 12 16 14"></polyline>
                         </svg>
-                        预计耗时 {{ Math.round(autoGeneratedRounds * 0.6) }} 分钟
+                        若Agent规模为100：预计耗时 {{ Math.round(autoGeneratedRounds * 0.6) }} 分钟
                       </span>
                     </div>
                     <div class="auto-desc">