feat: unify install.sh — single installer for framework + npm CLI

- tools/install.sh now installs both components:
  1. Framework (bash launcher, guides, runtime configs) → ~/.config/mosaic/
  2. @mosaic/cli (TUI, gateway client, wizard) → ~/.npm-global/
- Downloads framework from monorepo archive (no bootstrap repo dependency)
- Supports --framework, --cli, --check, --ref flags
- Delete remote-install.sh and remote-install.ps1 (redundant redirectors)
- Update all stale mosaic/bootstrap references → mosaic/mosaic-stack
- Update README.md with monorepo install instructions

Deprecates: mosaic/bootstrap repo

packages/mosaic/framework/bin/mosaic-release-upgrade

@@ -12,7 +12,7 @@ set -euo pipefail
 #   mosaic-release-upgrade --ref v0.2.0 --overwrite --yes
 
 MOSAIC_HOME="${MOSAIC_HOME:-$HOME/.config/mosaic}"
-REMOTE_SCRIPT_URL="${MOSAIC_REMOTE_INSTALL_URL:-https://git.mosaicstack.dev/mosaic/bootstrap/raw/branch/main/remote-install.sh}"
+REMOTE_SCRIPT_URL="${MOSAIC_REMOTE_INSTALL_URL:-https://git.mosaicstack.dev/mosaic/mosaic-stack/raw/branch/main/tools/install.sh}"
 BOOTSTRAP_REF="${MOSAIC_BOOTSTRAP_REF:-main}"
 INSTALL_MODE="${MOSAIC_INSTALL_MODE:-keep}" # keep|overwrite
 YES=false