feat(claude-cli): add dual-account setup with model/effort defaults

New extras service: installs the Claude Code CLI, creates separate
work/personal CLAUDE_CONFIG_DIR accounts behind claude-work/claude-personal
aliases, and applies settings.json defaults to both (model=claude-sonnet-5,
effortLevel=medium, ENABLE_PROMPT_CACHING_1H=1). A shared ~/.claude-shared/
CLAUDE.md holds the durable personal conventions (modular/reuse code,
numbered CLI menus with 0=exit, Playwright verification for UI changes)
and both accounts pull it in via @import so there's one copy to maintain.

Login itself (browser OAuth) can't be scripted - this only prepares the
directories/aliases/config; each account still needs one interactive
login. Tested fresh-install, rerun/cancel detection, and the jq settings
merge (preserves hand-added keys) in a scratch HOME.

README.md

@@ -190,7 +190,7 @@ a ready-to-copy Caddy config snippet to `~/docker/caddy-snippets/`.
 | `media` | `arm`, `audiobookshelf`, `calibre-web`, `emby`, `immich`, `jellyfin`, `lyrion` |
 | `cameras` | `frigate`, `frigate-audio`, `frigate-notify`, `sky-cam` |
 | `gaming` | `drum-rhythm-game`, `js99er`, `kyber-launcher`, `kyber-server`, `minecraft`, `wolf`, `wolf-pair` |
-| `extras` | `kdeconnect`, `silent-send`, `ssh-config`, `ssh-key-import` (import SSH public keys from GitHub/Launchpad, optionally lock down password auth — same step base.sh's required setup runs, re-runnable on its own), `sync-cc` |
+| `extras` | `kdeconnect`, `silent-send`, `ssh-config`, `ssh-key-import` (import SSH public keys from GitHub/Launchpad, optionally lock down password auth — same step base.sh's required setup runs, re-runnable on its own), `sync-cc`, `claude-cli` (Claude Code CLI — dual-account work/personal setup, model/effort defaults, shared global CLAUDE.md) |
 | `backup` | `backup` — complete recovery: entire `~/docker/<service>/` for every service via Kopia (Minecraft: flush+snap, no downtime; others: stop/snap/start for DB consistency), optional offsite mirror (`kopia repository sync-to`), plus `dr_bringup.sh` — unattended restore-everything-and-start for standing up a cold spare box; `borg-backup` — same coverage via Borg (chunk dedup, SSH remote repos, Borgmatic/Vorta compatible); `gaming-backup` — frequent game-save snapshots (Minecraft world data, emulator saves, Steam — no downtime, run hourly) |
 
 Run `./setup.sh --list` to see descriptions.
@@ -282,6 +282,7 @@ extras
   ssh-config
   ssh-key-import
   sync-cc
+  claude-cli
 
 backup
   backup