Change animation frames (#3627)

## Description
- Changes animation frames to be smaller
- Cleans up file names and popup logic

## tests
- Passes local CI

codex-rs/tui/frames/openai/frame_2.txt

@@ -0,0 +1,17 @@
+                                      
+             aeaenpnnnppa             
+         appeonpiiiniinaoiopa         
+       pioinooioaa  aoonoeiinip       
+     aieaeooppa           ppnieip     
+     paoeoainanna           apinip    
+    oepoa  ionpenp           nnioi    
+   piooi    aeiniaip          eoioi   
+   io na     pioiino          ioeei   
+   oooni    niaaaioeipppppppppiaiio   
+    anoi  eiio eo innaaaaeeaaipe i    
+    nnn o oneeio   aoooooooooipoii    
+     onaeep a              ppnepo     
+       enaaipp          pnap aio      
+        aianaaoopennnnenoaaiio        
+           aopopiiaaaaineoo           
+