fix: add aria-label attributes to emoji toolbar buttons

Screen readers cannot infer meaning from the bare emoji characters
(⚙, ＋, ⊞). Add aria-label to the two <button> elements and role=tab
plus aria-label to the Agent tab <div> so assistive technology
announces them correctly.

Author: VivanRajath

index.html

@@ -133,18 +133,18 @@ <h2>ClawLess</h2>
           <div class="resize-handle resize-v" id="resize-editor-terminal"></div>
           <div id="terminal-panel">
             <div id="terminal-tabs">
-              <div class="term-tab active" data-id="agent">
+              <div class="term-tab active" data-id="agent" role="tab" aria-label="Agent Terminal">
                 <span class="term-tab-label">⚙ Agent</span>
               </div>
-              <button id="btn-add-terminal" title="New Terminal">＋</button>
-              <button id="btn-split-terminal" class="btn-icon" title="Split Terminal">⊞</button>
+              <button id="btn-add-terminal" title="New Terminal" aria-label="New Terminal">＋</button>
+              <button id="btn-split-terminal" class="btn-icon" title="Split Terminal" aria-label="Split Terminal">⊞</button>
             </div>
             <div id="terminal-panes">
               <div class="term-pane active" id="terminal-pane-agent">
                 <div class="term-pane-inner" id="terminal-container"></div>
               </div>
-              <div class="resize-handle resize-h hidden" id="resize-terminal-split"></div>
-              <div class="term-pane hidden" id="terminal-pane-split">
+              <div class="resize-handle resize-h resize-split hidden" id="resize-terminal-split"></div>
+              <div class="term-pane term-pane-split hidden" id="terminal-pane-split">
                 <!-- Dynamic split pane content goes here -->
               </div>
             </div>