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/slug/frame_13.txt

@@ -0,0 +1,17 @@
+                                      
+                 5pppt                
+                 eddee                
+                 eedeg                
+                 epped                
+                 p  ee                
+                 gc-ee                
+                 t  ee                
+                 t  ge                
+                5t  dx-               
+                eg  toe               
+                pe-- xe               
+                 eddde                
+                 etted                
+                 pddeo                
+                 t -go                
+