REPL polish: line editor with history, cursor keys, tab completion

Replace bufio.Scanner with a proper terminal line editor (golang.org/x/term):

- Up/Down: history navigation (persisted to ~/.odek/repl_history)
- Left/Right/Home/End: cursor movement within line
- Backspace/Delete: character deletion
- Ctrl+U: clear line, Ctrl+K: delete to end
- Ctrl+L: clear screen, Ctrl+D: EOF, Ctrl+C: interrupt
- Tab: slash command completion (/exit, /help, /info, etc.)
- Bracketed paste: multi-line paste support
- Fallback to bufio.Scanner when terminal can't go raw

Author: jkyberneees

cmd/odek/repl.go

@@ -1,11 +1,11 @@
 package main
 
 import (
-	"bufio"
 	"context"
 	"fmt"
 	"os"
 	"os/signal"
+	"path/filepath"
 	"strings"
 
 	"github.com/BackendStack21/kode"
@@ -168,25 +168,40 @@ func replCmd(args []string) error {
 	ctx, cancel := signal.NotifyContext(context.Background(), os.Interrupt)
 	defer cancel()
 
-	scanner := bufio.NewScanner(os.Stdin)
 	turn := 0
+
+	// Line editor with history and tab completion for slash commands
+	editor := newReplEditor(
+		fmt.Sprintf("odek %d> ", turn+1),
+		[]string{
+			"/exit", "/quit", "/help", "/info",
+			"/sandbox", "/model", "/session",
+		},
+	)
+	editor.history.Load(filepath.Join(odekDir(), historyFilename))
 	for {
 		fmt.Fprintf(os.Stderr, "─── Turn %d ───\n", turn+1)
-		fmt.Fprint(os.Stderr, "> ")
 
-		if !scanner.Scan() {
+		input, err := editor.ReadLine()
+		if err != nil {
+			if err.Error() == "EOF" || err.Error() == "interrupt" {
+				fmt.Fprintf(os.Stderr, "\n")
+				break
+			}
 			break
 		}
-		input := strings.TrimSpace(scanner.Text())
+		input = strings.TrimSpace(input)
 
 		if input == "" {
+			turn++
 			continue
 		}
 
 		if strings.HasPrefix(input, "/") {
 			if handleREPLCommand(input, sess) {
 				break
 			}
+			turn++
 			continue
 		}