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/__insert_previous_path_head.fish

@@ -0,0 +1,11 @@
+function __insert_previous_path_head
+    # Get the last command tokens
+    set -l tokens (string split -n " " -- $history[1])
+    
+    # If there are tokens, take the last one and strip the 'tail'
+    if set -q tokens[-1]
+        set -l path_head (dirname -- $tokens[-1])
+        # Insert it into the current command line
+        commandline -i -- $path_head
+    end
+end

functions/__interactive_history_sub.fish

@@ -0,0 +1,17 @@
+function __interactive_history_sub
+    set -l current_line (commandline -b)
+    set -l last_cmd $history[1]
+    
+    if string match -qr '(.+)/(.+)' -- "$current_line"
+        set -l parts (string split '/' -- "$current_line")
+        set -l old $parts[1]
+        set -l new $parts[2]
+        set -l expanded (string replace -a -- "$old" "$new" "$last_cmd")
+        commandline -r "$expanded"
+    else
+        if test -z "$current_line"
+            commandline -r "sudo $last_cmd"
+        end
+    end
+    commandline -f repaint
+end

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

functions/expand_bang_all.fish

@@ -0,0 +1,11 @@
+function expand_bang_all
+    set -l token $argv[1]
+    if test -z "$token"; set token (commandline -t); end
+    
+    set -l tokens (string split -n " " -- $history[1])
+    if test (count $tokens) -gt 1
+        echo -- (string join " " -- $tokens[2..-1])
+    else
+        echo -- $token
+    end
+end

functions/expand_bang_caret.fish

@@ -0,0 +1,8 @@
+function expand_bang_caret
+    # Split the last history item into a list
+    set -l tokens (string split -n ' ' -- $history[1])
+    # tokens[1] is the command, tokens[2] is the first argument
+    if set -q tokens[2]
+        echo -- $tokens[2]
+    end
+end

functions/expand_bang_minus_n.fish

@@ -0,0 +1,17 @@
+function expand_bang_minus_n
+    set -l token $argv[1]
+    if test -z "$token"; set token (commandline -t); end
+    
+    # Extract the number from the regex match
+    if string match -qr '!-(\d+)' -- "$token"
+        set -l n (string match -r '!-(\d+)' -- "$token")[2]
+        
+        if test (count $history) -ge $n
+            echo -- $history[$n]
+        else
+            echo -- $token
+        end
+    else
+        echo -- $token
+    end
+end

functions/expand_bang_search.fish

@@ -0,0 +1,21 @@
+function expand_bang_search
+    set -l token $argv[1]
+    if test -z "$token"
+        set token (commandline -t)
+    end
+    
+    # Extract query: looks for text after !? and before an optional ?
+    set -l query (string match -r '!\?([^?]+)' -- $token)[2]
+    
+    if test -n "$query"
+        # Search history for a match anywhere in the command
+        set -l match (builtin history search --contains --max=1 -- $query)
+        
+        if test -n "$match"
+            echo -- $match
+            return
+        end
+    end
+    
+    echo -- $token
+end

functions/expand_bang_string.fish

@@ -0,0 +1,23 @@
+function expand_bang_string
+    # Fish 4.x passes the matched token as argv[1]
+    set -l token $argv[1]
+    if test -z "$token"
+        set token (commandline -t)
+    end
+    
+    # Remove the '!' to get the search query
+    set -l query (string sub -s 2 -- $token)
+    
+    if test -n "$query"
+        # Search history for a prefix match
+        set -l match (builtin history search --prefix --max=1 -- $query)
+        
+        if test -n "$match"
+            echo -- $match
+            return
+        end
+    end
+    
+    # If no match or empty query, return the token so it doesn't vanish
+        echo -- $token
+end

functions/expand_typo_sub.fish

@@ -0,0 +1,23 @@
+function expand_typo_sub
+    # In newer Fish, the matched token is often passed as $argv[1] 
+    # if the abbr is set up correctly. We'll fallback to commandline just in case.
+        set -l last_cmd $history[1]
+        set -l current_token $argv[1]
+        if test -z "$current_token"
+                set current_token (commandline -t)
+        end
+    
+        if string match -qr '\^([^^]+)\^([^^]*)' -- "$current_token"
+                set -l captured (string match -r '\^([^^]+)\^([^^]*)' -- "$current_token")
+                set -l old $captured[2]
+                set -l new $captured[3]
+        
+                if test -n "$old"
+                        # Using -- to ensure strings starting with '-' aren't treated as flags
+            echo -- (string replace -a -- "$old" "$new" "$last_cmd")
+        end
+    else
+        # Return the token itself so it doesn't vanish
+                echo -- "$current_token"
+        end
+end