fix: prevent workbench message overlap

web/hwlab-cloud-web/src/styles/workbench.css

@@ -576,14 +576,23 @@
   font-size: 16px;
 }
 
-.session-list,
-.conversation-panel {
+.session-list {
   display: grid;
   min-height: 0;
   gap: 6px;
   overflow: auto;
 }
 
+.conversation-panel {
+  display: flex;
+  min-height: 0;
+  min-width: 0;
+  flex-direction: column;
+  align-items: stretch;
+  gap: 6px;
+  overflow: auto;
+}
+
 .session-tab {
   display: grid;
   width: 100%;
@@ -622,13 +631,12 @@
 }
 
 .conversation-panel {
-  align-content: start;
   padding: 8px;
   scroll-behavior: smooth;
 }
 
 .conversation-empty-hint {
-  justify-self: center;
+  align-self: center;
   margin-top: 24px;
   color: #64748b;
   font-size: 13px;
@@ -636,15 +644,20 @@
 
 .message-card {
   position: relative;
-  display: grid;
-  align-self: start;
+  display: flex;
+  min-width: 0;
+  min-height: max-content;
+  flex: 0 0 auto;
+  flex-direction: column;
+  align-self: stretch;
   gap: 5px;
   border-radius: 4px;
   padding: 8px;
-  overflow: hidden;
+  overflow: visible;
 }
 
 .message-card[data-role="agent"] {
+  align-self: stretch;
   width: 100%;
 }
 
@@ -666,7 +679,7 @@
 }
 
 .message-card[data-role="user"] {
-  justify-self: end;
+  align-self: flex-end;
   width: max-content;
   min-width: min(120px, 100%);
   max-width: min(720px, 100%);