add: ai agent harnesses

currently copilot and opencode for starters, might be more

defaults/nvim/lua/plugins/mappings.lua

@@ -1,5 +1,7 @@
-local function toggle_floating_tui(cmd)
+local function toggle_tui(cmd, direction, size)
   local terminal
+  local dir = direction or "float"
+  local term_size = size
 
   return function()
     if not terminal then
@@ -8,17 +10,19 @@ local function toggle_floating_tui(cmd)
         cmd = cmd,
         hidden = true,
         close_on_exit = true,
-        direction = "float",
+        direction = dir,
         on_open = function() vim.cmd "startinsert!" end,
       }
     end
 
-    terminal:toggle()
+    terminal:toggle(term_size, dir)
   end
 end
 
-local toggle_k9s = toggle_floating_tui "k9s"
+local toggle_k9s = toggle_tui "k9s"
-local toggle_ghdash = toggle_floating_tui "gh-dash"
+local toggle_ghdash = toggle_tui "gh-dash"
+local toggle_ai_opencode = toggle_tui("opencode", "vertical", 80)
+local toggle_ai_copilot = toggle_tui("copilot", "vertical", 80)
 
 return {
   {
@@ -36,6 +40,15 @@ return {
             toggle_ghdash,
             desc = "GitHub dashboard",
           },
+          ["<Leader>a"] = { desc = "AI" },
+          ["<Leader>ao"] = {
+            toggle_ai_opencode,
+            desc = "opencode",
+          },
+          ["<Leader>ag"] = {
+            toggle_ai_copilot,
+            desc = "GH Copilot",
+          },
         },
       },
     },