feat!: unify mosaic CLI — native launcher, no bin/ directory

BREAKING CHANGE: ~/.config/mosaic/bin/ is removed entirely.
The mosaic npm CLI is now the only executable.

## What changed

- **bin/ → deleted**: All scripts moved to tools/_scripts/ (internal)
- **mosaic-launch → deleted**: Launcher logic is native TypeScript
  in packages/cli/src/commands/launch.ts
- **mosaic.ps1 → deleted**: PowerShell launcher removed
- **Framework install.sh**: Complete rewrite with migration system
- **Version tracking**: .framework-version file (schema v2)
- **Migration v1→v2**: Auto-removes bin/, cleans old PATH entries
  from shell profiles

## Native TypeScript launcher (commands/launch.ts)

All runtime launch logic ported from bash:
- Runtime prompt builder (AGENTS.md + RUNTIME.md + USER.md + TOOLS.md)
- Mission context injection (reads .mosaic/orchestrator/mission.json)
- PRD status injection (scans docs/PRD.md)
- Pre-flight checks (MOSAIC_HOME, AGENTS.md, SOUL.md, runtime binary)
- Session lock management with signal cleanup
- Per-runtime launch: Claude, Codex, OpenCode, Pi
- Yolo mode flags per runtime
- Pi skill discovery + extension loading
- Framework management (init, doctor, sync, bootstrap) delegates
  to tools/_scripts/ bash implementations

## Installer

- tools/install.sh: detects framework by .framework-version or AGENTS.md
- Framework install.sh: migration system with schema versioning
- Forward-compatible: add migrations as numbered blocks
- No PATH manipulation for framework (npm bin is the only PATH entry)

packages/mosaic/framework/tools/_scripts/mosaic-quality-verify

@@ -0,0 +1,52 @@
+#!/usr/bin/env bash
+set -euo pipefail
+
+MOSAIC_HOME="${MOSAIC_HOME:-$HOME/.config/mosaic}"
+TARGET_DIR="$(pwd)"
+
+usage() {
+  cat <<USAGE
+Usage: $(basename "$0") [--target <dir>]
+
+Run quality-rails verification checks inside a target repository.
+
+Examples:
+  $(basename "$0")
+  $(basename "$0") --target ~/src/my-project
+USAGE
+}
+
+while [[ $# -gt 0 ]]; do
+  case "$1" in
+    --target)
+      TARGET_DIR="${2:-}"
+      shift 2
+      ;;
+    -h|--help)
+      usage
+      exit 0
+      ;;
+    *)
+      echo "Unknown argument: $1" >&2
+      usage >&2
+      exit 1
+      ;;
+  esac
+done
+
+if [[ ! -d "$TARGET_DIR" ]]; then
+  echo "[mosaic-quality] Target directory does not exist: $TARGET_DIR" >&2
+  exit 1
+fi
+
+SCRIPT="$MOSAIC_HOME/tools/quality/scripts/verify.sh"
+if [[ ! -x "$SCRIPT" ]]; then
+  echo "[mosaic-quality] Missing verify script: $SCRIPT" >&2
+  exit 1
+fi
+
+echo "[mosaic-quality] Running verification in $TARGET_DIR"
+(
+  cd "$TARGET_DIR"
+  "$SCRIPT"
+)