feat(shell): add bash-style history expansions and interactive keybindings

- Replicate bash bang-operations (!^, !*, !string, etc.) via abbreviations
- Add Ctrl+G for previous path head insertion
- Add Ctrl+F for interactive history substitution
- Add Ctrl+Alt+U to quickly replace command tokens
- Update README documentation for all new features

functions/__substitute_typo.fish

@@ -0,0 +1,21 @@
+function __substitute_typo
+    set -l cursor_pos (commandline -C)
+    set -l cmd (commandline)
+    
+    # Check if the current line matches the ^old^new pattern
+    if string match -qr '\^([^^]+)\^([^^]*)' -- "$cmd"
+        set -l last_cmd $history[1]
+        set -l captured (string match -r '\^([^^]+)\^([^^]*)' -- "$cmd")
+        set -l old $captured[2]
+        set -l new $captured[3]
+        
+        if test -n "$old"
+            set -l expanded (string replace -a -- "$old" "$new" "$last_cmd")
+            commandline -r "$expanded"
+            # No need to move cursor, it's a whole new line
+                end
+        else
+                # If it's just a normal caret (not part of a pattern), just insert it
+        commandline -i '^'
+    end
+end