Feat: Implement openURL (zbirenbaum#311)

* Feat: Implement openURL

* feat: Use vim.ui.open

Author: Al0den

lua/copilot/api.lua

@@ -227,15 +227,28 @@ mod.handlers = {
   PanelSolutionsDone = panel.handlers.PanelSolutionsDone,
   statusNotification = status.handlers.statusNotification,
   ---@param result copilot_open_url_data
-  ["copilot/openURL"] = function(_, result)
-    vim.api.nvim_echo({
-      { "copilot/openURL" },
-      { vim.inspect({ _, result }) },
-      { "\n", "NONE" },
-    }, true, {})
-    error("not implemented: copilot.api.handlers['copilot/openURL']")
-  end,
+   ["copilot/openURL"] = function(_, result)
+    local success, _ = pcall(vim.ui.open, result.target)
+    if not success then
+      if vim.ui.open ~= nil then
+        vim.api.nvim_echo({
+            { "copilot/openURL" },
+            { vim.inspect({ _, result }) },
+            { "\n", "NONE" },
+        }, true, {})
+        error("Unsupported OS: vim.ui.open exists but failed to execute.")
+      else
+        vim.api.nvim_echo({
+            { "copilot/openURL" },
+            { vim.inspect({ _, result }) },
+            { "\n", "NONE" },
+        }, true, {})
+        error("Unsupported Version: vim.ui.open requires Neovim > 0.10")
+      end
+    end
+  end
 }
+
 mod.panel = panel
 mod.status = status