fix: TUI CSI u key parsing and console escape sequence order

- TUI: Add parseCSIuBytes to handle CSI u sequences that bubbletea
  v1.3.6 returns as []byte (unknownCSISequenceMsg). Parses codepoint
  and modifier bits to reconstruct key string for hotkey routing.
- Console: Reorder escape parser checks. Check 2-byte non-CSI
  sequences first, then CSI terminator only after ESC[ introducer.
  Fixes CSI u sequences being truncated at '[' byte (0x5b).

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

internal/tui/hotkeys.go

@@ -1,6 +1,7 @@
 package tui
 
 import (
+	"strconv"
 	"strings"
 
 	tea "github.com/charmbracelet/bubbletea"
@@ -146,3 +147,35 @@ func completionBase(line string) string {
 	}
 	return line[:i+1]
 }
+
+func parseCSIuBytes(b []byte) (string, bool) {
+	s := string(b)
+	if !strings.HasPrefix(s, "\x1b[") || !strings.HasSuffix(s, "u") {
+		return "", false
+	}
+	inner := s[2 : len(s)-1]
+	parts := strings.SplitN(inner, ";", 2)
+	if len(parts) != 2 {
+		return "", false
+	}
+	cp, err := strconv.Atoi(parts[0])
+	if err != nil || cp < 'a' || cp > 'z' {
+		return "", false
+	}
+	mod, err := strconv.Atoi(parts[1])
+	if err != nil {
+		return "", false
+	}
+	var seq []string
+	if mod&4 != 0 {
+		seq = append(seq, "ctrl")
+	}
+	if mod&2 != 0 {
+		seq = append(seq, "alt")
+	}
+	if mod&1 != 0 {
+		seq = append(seq, "shift")
+	}
+	seq = append(seq, string(rune(cp)))
+	return strings.Join(seq, "+"), true
+}