style(install): KeiSei brand colors + ASCII banner in installer output

- KEISEI ASCII logo (голубой) shown at install start via kei_banner().
- `[install]` prefix → тёмно-жёлтый (38;5;178); primitive names → голубой
  (38;5;39) in both the plan and the per-primitive install lines.
- Language menu: code голубой, native name тёмно-жёлтый.
- lib-log COLOR now enables under curl|bash too: detect terminal via
  `[ -t 1 ] || /dev/tty` (web-install tees stdout → -t 1 false → colors were
  silently off). This is color detection, not an interactivity gate (pairs
  with no -t 0 — does not violate tty-interactivity-gate rule).

Verified piped-under-pty: banner + gold [install] + blue/gold language menu
all render through the tee logfile.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

install.sh

@@ -203,6 +203,7 @@ if ! printf '%s\n' "$CONFIRM_INPUT" | show_confirm_screen "$CONFIRM_LABEL"; then
 fi
 
 # --- execute install phases ----------------------------------------------
+kei_banner
 setup_target_dirs
 scaffold_memory_index
 install_blocks

install/lib-log.sh

@@ -1,21 +1,43 @@
 # shellcheck shell=bash
-# lib-log.sh — say / warn / err with optional ANSI color.
-# Honors NO_COLOR (no-color.org) and TTY detection on fd 1.
+# lib-log.sh — say / warn / err with optional ANSI color + KeiSei banner.
+# Honors NO_COLOR (no-color.org). Color is ON when stdout is a TTY OR a
+# controlling terminal is reachable via /dev/tty — the latter matters under
+# `curl|bash`, where web-install.sh tees stdout (so `-t 1` is false even in an
+# interactive session, but the terminal is still there via /dev/tty).
+# This `-t 1`-with-/dev/tty test is COLOR detection, NOT an interactivity gate
+# (see ~/.claude/rules/tty-interactivity-gate.md) — it pairs with no `-t 0`.
 # Sourced by install.sh; no top-level execution.
 
-# ANSI on iff stdout is a TTY and NO_COLOR is unset.
-if [ -t 1 ] && [ "${NO_COLOR:-}" = "" ]; then
+if { [ -t 1 ] || { : < /dev/tty; } 2>/dev/null; } && [ "${NO_COLOR:-}" = "" ]; then
   COLOR=1
 else
   COLOR=0
 fi
 
+# Brand palette: тёмно-жёлтый (gold) for [install], голубой (sky-blue) for KeiSei.
 if [ "$COLOR" = "1" ]; then
-  say()  { printf '\033[1;36m[install]\033[0m %s\n' "$*"; }
+  KEI_GOLD=$'\033[38;5;178m'    # тёмно-жёлтый — install prefix
+  KEI_BLUE=$'\033[38;5;39m'     # голубой — logo / primitives
+  KEI_DIM=$'\033[2m'
+  KEI_RST=$'\033[0m'
+  say()  { printf '%s[install]%s %s\n' "$KEI_GOLD" "$KEI_RST" "$*"; }
   warn() { printf '\033[1;33m[warn]\033[0m %s\n' "$*"; }
   err()  { printf '\033[1;31m[error]\033[0m %s\n' "$*" >&2; }
 else
+  KEI_GOLD= KEI_BLUE= KEI_DIM= KEI_RST=
   say()  { printf '[install] %s\n' "$*"; }
   warn() { printf '[warn] %s\n' "$*"; }
   err()  { printf '[error] %s\n' "$*" >&2; }
 fi
+
+# KeiSei ASCII banner — голубой logo, shown once at install start.
+kei_banner() {
+  printf '\n'
+  printf '%s    ██╗  ██╗███████╗██╗███████╗███████╗██╗%s\n' "$KEI_BLUE" "$KEI_RST"
+  printf '%s    ██║ ██╔╝██╔════╝██║██╔════╝██╔════╝██║%s\n' "$KEI_BLUE" "$KEI_RST"
+  printf '%s    █████╔╝ █████╗  ██║███████╗█████╗  ██║%s\n' "$KEI_BLUE" "$KEI_RST"
+  printf '%s    ██╔═██╗ ██╔══╝  ██║╚════██║██╔══╝  ██║%s\n' "$KEI_BLUE" "$KEI_RST"
+  printf '%s    ██║  ██╗███████╗██║███████║███████╗██║%s\n' "$KEI_BLUE" "$KEI_RST"
+  printf '%s    ╚═╝  ╚═╝╚══════╝╚═╝╚══════╝╚══════╝╚═╝%s\n' "$KEI_BLUE" "$KEI_RST"
+  printf '%s    KeiSeiKit · installing%s\n\n' "$KEI_GOLD" "$KEI_RST"
+}

install/lib-onboarding-ui.sh

@@ -57,7 +57,7 @@ onboarding_pick_language() {
     while IFS=$'\t' read -r code name; do
       [ -z "$code" ] && continue
       codes+=("$code")
-      printf "  %2d) %s — %s\n" "$i" "$code" "$name" >&2
+      printf "  %2d) ${KEI_BLUE:-}%s${KEI_RST:-} — ${KEI_GOLD:-}%s${KEI_RST:-}\n" "$i" "$code" "$name" >&2
       i=$((i+1))
     done <<< "$langs"
     ans="$(_onb_read_choice "${#codes[@]}" "[1-${#codes[@]}, default 1=en]: ")"

install/lib-plan.sh

@@ -100,7 +100,7 @@ _print_primitive_rows() {
     [ -z "$name" ] && continue
     kind="$(primitive_field "$name" kind 2>/dev/null || echo '?')"
     extra="$(primitive_time_secs "$name")s, $(( $(primitive_disk_kb "$name") / 1024 )) MB"
-    printf '  + %-22s (%s, ~%s)\n' "$name" "$kind" "$extra"
+    printf '  + %s%-22s%s (%s, ~%s)\n' "${KEI_BLUE:-}" "$name" "${KEI_RST:-}" "$kind" "$extra"
   done
 }
 

install/lib-primitives.sh

@@ -28,7 +28,7 @@ copy_shell_primitive() {
   mkdir -p "$AGENTS_DIR/_primitives"
   cp -f "$src" "$dst"
   chmod +x "$dst"
-  say "  + shell: $name ($file)"
+  say "  + shell: ${KEI_BLUE:-}$name${KEI_RST:-} ($file)"
 }
 
 remove_shell_primitive() {
@@ -65,7 +65,7 @@ copy_rust_primitive() {
       cp -rf "$src/$sibling/"* "$dst/$sibling/" 2>/dev/null || true
     fi
   done
-  say "  + rust:  $name (crate $crate)"
+  say "  + rust:  ${KEI_BLUE:-}$name${KEI_RST:-} (crate $crate)"
 }
 
 remove_rust_primitive() {
@@ -103,7 +103,7 @@ copy_node_primitive() {
       find "$dst" -depth -name "$ex" -exec rm -rf {} + 2>/dev/null || true
     done < <(_node_excludes)
   fi
-  say "  + node:  $name (path $rel)"
+  say "  + node:  ${KEI_BLUE:-}$name${KEI_RST:-} (path $rel)"
 }
 
 remove_node_primitive() {
@@ -171,7 +171,7 @@ install_external_primitive() {
     err "external primitive $name: entry point $slug not found in $file"
     return 1
   fi
-  say "  + external: $name (via $file)"
+  say "  + external: ${KEI_BLUE:-}$name${KEI_RST:-} (via $file)"
   "$slug" || warn "$name install failed — re-run after fixing prereqs"
 }