Use legible figlet block-art banner (CLEANUP SERVER) with per-line rainbow

Replaces the gradient-bar version with proper figlet-style ASCII art
so the title is actually readable; each line colored in a rainbow
gradient, with a Vietnamese subtitle.

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

cleanup-server

@@ -18,39 +18,35 @@ else
 fi
 
 # -----------------------------
-# Banner rainbow nhưng đọc được: thanh gradient + tiêu đề rõ
+# Banner rainbow (ASCII art figlet, per-line gradient)
 # -----------------------------
-repeat_char() {
-    # $1 = số lượng, $2 = ký tự
-    printf "%${1}s" "" | tr ' ' "$2"
-}
-
-# In 1 thanh block gradient rainbow (TTY) hoặc '#' (non-TTY)
-rainbow_bar() {
-    local width="$1"
-    if [ -t 1 ]; then
-        local -a codes=(51 87 123 159 220 214 209 204)
-        local n=${#codes[@]} seg i line=""
-        for ((i = 0; i < n; i++)); do
-            seg=$(( (width + n - 1 - i) / n ))
-            line+="$(printf '\033[1;38;5;%dm' "${codes[$i]}")""$(repeat_char "$seg" "█")"
-        done
-        printf '%s%s\n' "$line" "$C_RESET"
-    else
-        repeat_char "$width" "#"
-        echo
-    fi
-}
-
 print_banner() {
+    local -a lines=(
+        '▗▄▄▄▖▗▖        ▗▄▄▖▗▄▄▄▖▗▄▄▖ ▗▖  ▗▖▗▄▄▄▖▗▄▄▖      ▗▄▄▖▗▖   ▗▄▄▄▖ ▗▄▖ ▗▖  ▗▖▗▄▄▄▖▗▄▖ '
+        '  █  ▐▌       ▐▌   ▐▌   ▐▌ ▐▌▐▌  ▐▌▐▌   ▐▌ ▐▌    ▐▌   ▐▌   ▐▌   ▐▌ ▐▌▐▛▚▖▐▌▐▌   ▐▌ ▐▌'
+        '  █  ▐▌        ▝▀▚▖▐▛▀▀▘▐▛▀▚▖▐▌  ▐▌▐▛▀▀▘▐▛▀▚▖    ▐▌   ▐▌   ▐▛▀▀▘▐▛▀▜▌▐▌ ▝▜▌▐▛▀▀▘▐▛▀▚▖'
+        '  █  ▐▙▄▄▖    ▗▄▄▞▘▐▙▄▄▖▐▌ ▐▌ ▝▚▞▘ ▐▙▄▄▖▐▌ ▐▌    ▝▚▄▄▖▐▙▄▄▖▐▙▄▄▖▐▌ ▐▌▐▌  ▐▌▐▙▄▄▖▐▌ ▐▌'
+    )
+    local -a colors=()
+    if [ -t 1 ]; then
+        colors=(
+            $'\033[1;38;5;51m'    # cyan
+            $'\033[1;38;5;120m'   # xanh lá
+            $'\033[1;38;5;220m'   # vàng gold
+            $'\033[1;38;5;209m'   # cam-đỏ
+        )
+    fi
     echo ""
-    rainbow_bar 56
-    echo ""
-    printf '  %s🧹  CLEANUP-SERVER%s\n' "$C_TITLE" "$C_RESET"
+    local i
+    for ((i = 0; i < ${#lines[@]}; i++)); do
+        if [ -t 1 ]; then
+            printf '%s%s%s\n' "${colors[$i]}" "${lines[$i]}" "$C_RESET"
+        else
+            printf '%s\n' "${lines[$i]}"
+        fi
+    done
     printf '  %sDọn dẹp + nâng cấp server (Ubuntu / Arch)%s\n' "$C_WARN" "$C_RESET"
     echo ""
-    rainbow_bar 56
-    echo ""
 }
 
 # -----------------------------