Fix copy button selectors and message input handling in GitHub Copilot and Grok content scripts

- in `apps/browser/src/content-scripts/send-prompt-content-script/chatbots/grok.ts`, implement wait until ready with the approach seen in `apps/browser/src/content-scripts/send-prompt-content-script/chatbots/chatgpt.ts`

└── apps
    └── browser
        └── src
            └── content-scripts
                └── send-prompt-content-script
                    └── chatbots
                        ├── chatgpt.ts
                        └── grok.ts

Author: robertpiosik

apps/browser/src/content-scripts/send-prompt-content-script/chatbots/github-copilot.ts

@@ -42,7 +42,7 @@ export const github_copilot: Chatbot = {
         get_chat_turn: (f) => f.closest('div.message-container') as HTMLElement,
         perform_copy: (f) => {
           const copy_button = f.querySelector(
-            'button:nth-child(5)'
+            'button:nth-of-type(3)'
           ) as HTMLElement
           if (!copy_button) {
             report_initialization_error({

apps/browser/src/content-scripts/send-prompt-content-script/chatbots/grok.ts

@@ -18,7 +18,6 @@ export const grok: Chatbot = {
       }
       check_for_element()
     })
-    await new Promise((r) => setTimeout(r, 500))
   },
   set_options: async (chat) => {
     const options = chat.options
@@ -52,7 +51,7 @@ export const grok: Chatbot = {
       return
     }
 
-    input_element.textContent = params.message
+    input_element.innerText = params.message
     input_element.dispatchEvent(new Event('input', { bubbles: true }))
     input_element.focus()
   },
@@ -65,7 +64,7 @@ export const grok: Chatbot = {
         get_chat_turn: (f) => f.closest('.items-start'),
         perform_copy: (f) => {
           const copy_button = f.querySelector(
-            'button:nth-child(4)'
+            'button:first-child'
           ) as HTMLElement
           if (!copy_button) {
             report_initialization_error({