Refactor conversation sidebar and update UI components for improved usability

- Updated `smoke-disciplinas-browser.mjs` to change the locator for the new chat button, enhancing element visibility.
- Refactored `theme.css` to remove outdated styles and improve the layout of the conversation sidebar, including adjustments to sidebar width and padding.
- Enhanced `entrance.js`, `ui.js`, and `ChatView.js` to remove references to the old new chat button and streamline the initialization process.
- Introduced new elements in `ConversationSidebar.js` for better menu handling and user interactions, including a context menu for conversation actions.
- Updated `index.html` to reflect the new sidebar structure and improve accessibility features for navigation elements.

Author: GaabDevWeb

bin/smoke-disciplinas-browser.mjs

@@ -168,7 +168,7 @@ async function waitForOnline(page, timeoutMs = 90_000) {
 
 async function newConversation(page) {
   await waitForOnline(page).catch(() => {});
-  const newChat = page.locator("#new-chat-button");
+  const newChat = page.locator("#sidebar-new-chat");
   if (await newChat.isVisible().catch(() => false)) {
     await newChat.click();
   } else {