feat: improve install script with banner, progress bar, and colors

Add visual banner, step indicators (✓/▸/✗), and curl progress bar
for the binary download. Small files stay silent.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

Author: Frank Guo

scripts/install.sh

@@ -10,16 +10,44 @@ if [[ -t 1 ]]; then
     GREEN='\033[0;32m'
     YELLOW='\033[0;33m'
     BLUE='\033[0;34m'
+    CYAN='\033[0;36m'
+    DIM='\033[2m'
     BOLD='\033[1m'
     NC='\033[0m'
 else
-    RED='' GREEN='' YELLOW='' BLUE='' BOLD='' NC=''
+    RED='' GREEN='' YELLOW='' BLUE='' CYAN='' DIM='' BOLD='' NC=''
 fi
 
-info()    { printf '%b%s%b\n' "${BLUE}==>${NC} ${BOLD}" "$1" "${NC}"; }
-success() { printf '%b%s%b\n' "${GREEN}==>${NC} ${BOLD}" "$1" "${NC}"; }
-warn()    { printf '%b %s\n' "${YELLOW}Warning:${NC}" "$1"; }
-error()   { printf '%b %s\n' "${RED}Error:${NC}" "$1" >&2; exit 1; }
+info()    { printf '  %b%s%b %s\n' "${BLUE}" "▸" "${NC}" "$1"; }
+success() { printf '  %b%s%b %s\n' "${GREEN}" "✓" "${NC}" "$1"; }
+warn()    { printf '  %b%s%b %s\n' "${YELLOW}" "!" "${NC}" "$1"; }
+error()   { printf '  %b%s%b %s\n' "${RED}" "✗" "${NC}" "$1" >&2; exit 1; }
+
+banner() {
+    echo ""
+    printf '%b' "${CYAN}${BOLD}"
+    echo "  ┌─────────────────────────────────┐"
+    echo "  │         rekal installer          │"
+    echo "  └─────────────────────────────────┘"
+    printf '%b' "${NC}"
+    echo ""
+}
+
+# Download with progress bar for interactive terminals, silent otherwise.
+download_with_progress() {
+    local url="$1" dest="$2" label="$3"
+    info "${label}"
+    if [[ -t 1 ]]; then
+        curl -fL --progress-bar "$url" -o "$dest"
+    else
+        curl -fsSL "$url" -o "$dest"
+    fi
+}
+
+# Silent download for small files.
+download_silent() {
+    curl -fsSL "$1" -o "$2"
+}
 
 detect_os() {
     case "$(uname -s | tr '[:upper:]' '[:lower:]')" in
@@ -55,10 +83,6 @@ get_version() {
     echo "$version"
 }
 
-download_file() {
-    curl -fsSL "$1" -o "$2"
-}
-
 verify_checksum() {
     local file="$1" expected="$2" actual
     if command -v sha256sum &>/dev/null; then
@@ -73,16 +97,20 @@ verify_checksum() {
 }
 
 main() {
+    banner
+
     command -v curl &>/dev/null || error "curl is required. Install curl and try again."
 
     # Require Claude Code — check binary on PATH or config directory.
     if ! command -v claude &>/dev/null && [[ ! -d "${HOME}/.claude" ]]; then
         echo ""
-        echo -e "${RED}Error:${NC} Rekal requires Claude Code, which was not detected on this system."
-        echo "For the beta release, only Claude Code is supported. Other coding agents will be supported in a future release."
+        echo -e "  ${RED}✗${NC} Rekal requires Claude Code, which was not detected on this system."
+        echo "    For the beta release, only Claude Code is supported."
+        echo "    Other coding agents will be supported in a future release."
+        echo ""
+        echo -e "    Install Claude Code: ${BOLD}https://docs.anthropic.com/en/docs/claude-code${NC}"
+        echo -e "    Rekal docs:          ${BOLD}https://github.com/rekal-dev/rekal-cli${NC}"
         echo ""
-        echo "  Install Claude Code: https://docs.anthropic.com/en/docs/claude-code"
-        echo "  Rekal docs:          https://github.com/rekal-dev/rekal-cli"
         exit 1
     fi
 
@@ -102,15 +130,14 @@ main() {
 
     local install_dir="${target_dir:-${DEFAULT_INSTALL_DIR}}"
 
-    info "Installing Rekal CLI..."
     local os arch version
     os=$(detect_os)
     arch=$(detect_arch)
-    info "Detected platform: ${os}/${arch}"
+    success "Platform: ${os}/${arch}"
 
     info "Resolving version..."
     version=$(get_version "${version_arg:-}")
-    info "Version: ${version}"
+    success "Version: ${BOLD}v${version}${NC}"
 
     local archive_name="rekal_${os}_${arch}.tar.gz"
     local download_url="https://github.com/${GITHUB_REPO}/releases/download/v${version}/${archive_name}"
@@ -121,18 +148,17 @@ main() {
     REKAL_TMP_DIR="$tmp_dir"
     trap 'rm -rf "${REKAL_TMP_DIR:-}"' EXIT
 
-    info "Downloading ${archive_name}..."
-    download_file "$download_url" "${tmp_dir}/${archive_name}" || error "Download failed: $download_url"
+    echo ""
+    download_with_progress "$download_url" "${tmp_dir}/${archive_name}" "Downloading ${archive_name}..." \
+        || error "Download failed: $download_url"
 
-    info "Downloading checksums..."
-    download_file "$checksums_url" "${tmp_dir}/checksums.txt" || error "Failed to download checksums."
+    download_silent "$checksums_url" "${tmp_dir}/checksums.txt" || error "Failed to download checksums."
 
-    info "Verifying checksum..."
     local expected
     expected=$(grep -E "${archive_name}\$" "${tmp_dir}/checksums.txt" | awk '{print $1}' || true)
     [[ -z "$expected" ]] && error "Checksum for ${archive_name} not found in checksums.txt."
     verify_checksum "${tmp_dir}/${archive_name}" "$expected"
-    success "Checksum OK"
+    success "Checksum verified"
 
     info "Extracting..."
     tar -xzf "${tmp_dir}/${archive_name}" -C "$tmp_dir"
@@ -146,7 +172,8 @@ main() {
     mv "$binary_path" "$install_path"
 
     if "$install_path" version &>/dev/null; then
-        success "Rekal CLI installed to ${install_path}"
+        echo ""
+        success "Installed to ${BOLD}${install_path}${NC}"
     else
         error "Binary failed to run after install."
     fi
@@ -155,18 +182,20 @@ main() {
     path_binary=$(command -v rekal 2>/dev/null || true)
     if [[ -n "$path_binary" && "$path_binary" != "$install_path" ]]; then
         echo ""
-        echo -e "${YELLOW}!${NC} ${BOLD}PATH conflict:${NC} 'rekal' resolves to ${path_binary}, not ${install_path}"
-        echo -e "  Adjust PATH or remove the other binary."
+        warn "${BOLD}PATH conflict:${NC} 'rekal' resolves to ${path_binary}, not ${install_path}"
+        echo "    Adjust PATH or remove the other binary."
         exit 1
     fi
 
     if [[ -z "$path_binary" ]]; then
         echo ""
-        echo -e "  ${YELLOW}Add to PATH to run \`rekal\` from anywhere:${NC}"
+        echo -e "  ${DIM}Add to PATH to run rekal from anywhere:${NC}"
         echo -e "    ${BOLD}export PATH=\"${install_dir}:\$PATH\"${NC}"
         echo ""
-        echo "  Then run: rekal version"
+        echo -e "  ${DIM}Then run:${NC} ${BOLD}rekal version${NC}"
     fi
+
+    echo ""
 }
 
 main "$@"