feat(setup): brand setup:auto with @clack/prompts + brand palette

Wraps the scripted setup flow in a branded, friendly UI. Each step runs
under a clack spinner with elapsed time; child stdout/stderr is captured
quietly and dumped only on failure. Interactive children (token paste,
Anthropic OAuth) bypass the spinner and inherit the TTY.

- intro: NanoClaw wordmark + brand-cyan accent chip, truecolor with
  kleur fallback and NO_COLOR / non-TTY awareness
- pair-telegram: emits PAIR_TELEGRAM_CODE / _ATTEMPT status blocks only;
  auto.ts renders clack notes + "received X — doesn't match" checkpoints
- streaming status-block parser handles mid-step events without waiting
  for the child to exit
- terminal-block detection now finds any block with a STATUS field
  (handles MOUNTS emitting CONFIGURE_MOUNTS, etc.) and treats 'skipped'
  as a success variant with an optional friendlier label

Also fixes a latent bash bug where `$VAR…` (unbraced followed by a
multi-byte Unicode character) pulled ellipsis bytes into the variable
name lookup and tripped `set -u`. Braced `${VAR}` in add-telegram.sh
and register-claude-token.sh.

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

setup/add-telegram.sh

@@ -27,7 +27,7 @@ if need_install; then
 
   # pair-telegram.ts is maintained in this branch (setup-auto), so it's NOT
   # in this list — do not overwrite the local version with the channels copy.
-  echo "[add-telegram] Copying adapter files from $CHANNELS_BRANCH…"
+  echo "[add-telegram] Copying adapter files from ${CHANNELS_BRANCH}…"
   for f in \
     src/channels/telegram.ts \
     src/channels/telegram-pairing.ts \
@@ -59,7 +59,7 @@ if need_install; then
     }
   '
 
-  echo "[add-telegram] Installing $ADAPTER_VERSION…"
+  echo "[add-telegram] Installing ${ADAPTER_VERSION}…"
   pnpm install "$ADAPTER_VERSION"
 
   echo "[add-telegram] Building…"