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-link-runtime-assets

@@ -0,0 +1,136 @@
+#!/usr/bin/env bash
+set -euo pipefail
+
+MOSAIC_HOME="${MOSAIC_HOME:-$HOME/.config/mosaic}"
+backup_stamp="$(date +%Y%m%d%H%M%S)"
+
+copy_file_managed() {
+  local src="$1"
+  local dst="$2"
+
+  mkdir -p "$(dirname "$dst")"
+
+  if [[ -L "$dst" ]]; then
+    rm -f "$dst"
+  fi
+
+  if [[ -f "$dst" ]]; then
+    if cmp -s "$src" "$dst"; then
+      return
+    fi
+    mv "$dst" "${dst}.mosaic-bak-${backup_stamp}"
+  fi
+
+  cp "$src" "$dst"
+}
+
+remove_legacy_path() {
+  local p="$1"
+
+  if [[ -L "$p" ]]; then
+    rm -f "$p"
+    return
+  fi
+
+  if [[ -d "$p" ]]; then
+    find "$p" -depth -type l -delete 2>/dev/null || true
+    find "$p" -depth -type d -empty -delete 2>/dev/null || true
+    return
+  fi
+
+  # Remove stale symlinked files if present.
+  if [[ -e "$p" && -L "$p" ]]; then
+    rm -f "$p"
+  fi
+}
+
+# Remove compatibility symlink surfaces for migrated content.
+legacy_paths=(
+  "$HOME/.claude/agent-guides"
+  "$HOME/.claude/scripts/git"
+  "$HOME/.claude/scripts/codex"
+  "$HOME/.claude/scripts/bootstrap"
+  "$HOME/.claude/scripts/cicd"
+  "$HOME/.claude/scripts/portainer"
+  "$HOME/.claude/scripts/debug-hook.sh"
+  "$HOME/.claude/scripts/qa-hook-handler.sh"
+  "$HOME/.claude/scripts/qa-hook-stdin.sh"
+  "$HOME/.claude/scripts/qa-hook-wrapper.sh"
+  "$HOME/.claude/scripts/qa-queue-monitor.sh"
+  "$HOME/.claude/scripts/remediation-hook-handler.sh"
+  "$HOME/.claude/templates"
+  "$HOME/.claude/presets/domains"
+  "$HOME/.claude/presets/tech-stacks"
+  "$HOME/.claude/presets/workflows"
+  "$HOME/.claude/presets/jarvis-loop.json"
+)
+
+for p in "${legacy_paths[@]}"; do
+  remove_legacy_path "$p"
+done
+
+# Claude-specific runtime files (settings, hooks — NOT CLAUDE.md which is now a thin pointer)
+for runtime_file in \
+  CLAUDE.md \
+  settings.json \
+  hooks-config.json \
+  context7-integration.md; do
+  src="$MOSAIC_HOME/runtime/claude/$runtime_file"
+  [[ -f "$src" ]] || continue
+  copy_file_managed "$src" "$HOME/.claude/$runtime_file"
+done
+
+# OpenCode runtime adapter (thin pointer to AGENTS.md)
+opencode_adapter="$MOSAIC_HOME/runtime/opencode/AGENTS.md"
+if [[ -f "$opencode_adapter" ]]; then
+  copy_file_managed "$opencode_adapter" "$HOME/.config/opencode/AGENTS.md"
+fi
+
+# Codex runtime adapter (thin pointer to AGENTS.md)
+codex_adapter="$MOSAIC_HOME/runtime/codex/instructions.md"
+if [[ -f "$codex_adapter" ]]; then
+  mkdir -p "$HOME/.codex"
+  copy_file_managed "$codex_adapter" "$HOME/.codex/instructions.md"
+fi
+
+# Pi runtime settings (MCP + skills paths)
+pi_settings_dir="$HOME/.pi/agent"
+pi_settings_file="$pi_settings_dir/settings.json"
+mkdir -p "$pi_settings_dir"
+
+if [[ ! -f "$pi_settings_file" ]]; then
+  echo '{}' > "$pi_settings_file"
+fi
+
+# Ensure Pi settings.json has Mosaic skills paths
+mosaic_skills_path="$MOSAIC_HOME/skills"
+mosaic_local_path="$MOSAIC_HOME/skills-local"
+if ! grep -q "$mosaic_skills_path" "$pi_settings_file" 2>/dev/null; then
+  if command -v python3 >/dev/null 2>&1; then
+    python3 -c "
+import json
+with open('$pi_settings_file', 'r') as f:
+    data = json.load(f)
+skills = data.get('skills', [])
+if not isinstance(skills, list):
+    skills = []
+for p in ['$mosaic_skills_path', '$mosaic_local_path']:
+    if p not in skills:
+        skills.append(p)
+data['skills'] = skills
+with open('$pi_settings_file', 'w') as f:
+    json.dump(data, f, indent=2)
+    f.write('\\n')
+" 2>/dev/null
+  fi
+fi
+
+# Pi extension is loaded via --extension flag in the mosaic launcher.
+# Do NOT copy into ~/.pi/agent/extensions/ — that causes duplicate loading.
+
+if [[ -x "$MOSAIC_HOME/tools/_scripts/mosaic-ensure-sequential-thinking" ]]; then
+  "$MOSAIC_HOME/tools/_scripts/mosaic-ensure-sequential-thinking"
+fi
+
+echo "[mosaic-link] Runtime assets synced (non-symlink mode)"
+echo "[mosaic-link] Canonical source: $MOSAIC_HOME"