fix: prevent composer action bar from overlaying text field

Change the bottom action bar from absolute positioning to normal
document flow so it sits below the editable area instead of floating
on top. Reduce editable bottom padding since buttons no longer overlap.

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

src/renderer/components/ChatPane.tsx

@@ -617,9 +617,9 @@ export function ChatPane({
               }
             >
               {/* Bottom action bar: left = shortcuts, right = buttons */}
-              <div className="absolute inset-x-2 bottom-2 flex items-center justify-between pointer-events-none">
+              <div className="flex items-center justify-between px-2 pb-2">
                 {/* Left: quick actions */}
-                <div className="flex items-center gap-1.5 pointer-events-auto">
+                <div className="flex items-center gap-1.5">
                   {onTerminalToggle && (
                     <InlineTerminalPill
                       disabled={false}
@@ -638,7 +638,7 @@ export function ChatPane({
                 </div>
 
                 {/* Right: attach, plan mode, send */}
-                <div className="flex items-center gap-1 pointer-events-auto">
+                <div className="flex items-center gap-1">
                 {/* Attachment picker */}
                 <button
                   aria-label="Attach image"

src/renderer/styles.css

@@ -145,7 +145,7 @@ body {
   min-height: 52px;
   max-height: 200px;
   overflow-y: auto;
-  padding: 10px 48px 10px 16px;
+  padding: 10px 16px 4px 16px;
   font-size: 14px;
   line-height: 1.6;
   color: #f4f4f5;