centralize guides and rails under mosaic with runtime compatibility links

bin/mosaic-bootstrap-repo

@@ -73,6 +73,11 @@ bash scripts/agent/critical.sh
 bash scripts/agent/session-end.sh
 ```
 
+## Shared Rails
+
+- Quality and orchestration guides: `~/.mosaic/guides/`
+- Shared automation rails: `~/.mosaic/rails/`
+
 ## Repo-Specific Notes
 
 - Add project constraints and workflows here.

bin/mosaic-link-runtime-assets

@@ -0,0 +1,65 @@
+#!/usr/bin/env bash
+set -euo pipefail
+
+MOSAIC_HOME="${MOSAIC_HOME:-$HOME/.mosaic}"
+
+backup_stamp="$(date +%Y%m%d%H%M%S)"
+
+link_file() {
+  local src="$1"
+  local dst="$2"
+
+  mkdir -p "$(dirname "$dst")"
+
+  if [[ -L "$dst" ]]; then
+    local cur
+    cur="$(readlink -f "$dst" 2>/dev/null || true)"
+    local want
+    want="$(readlink -f "$src" 2>/dev/null || true)"
+    if [[ -n "$cur" && -n "$want" && "$cur" == "$want" ]]; then
+      return
+    fi
+    rm -f "$dst"
+  elif [[ -e "$dst" ]]; then
+    mv "$dst" "${dst}.mosaic-bak-${backup_stamp}"
+  fi
+
+  ln -s "$src" "$dst"
+}
+
+link_tree_files() {
+  local src_root="$1"
+  local dst_root="$2"
+
+  [[ -d "$src_root" ]] || return
+
+  while IFS= read -r -d '' src; do
+    local rel
+    rel="${src#$src_root/}"
+    local dst="$dst_root/$rel"
+    link_file "$src" "$dst"
+  done < <(find "$src_root" -type f -print0)
+}
+
+# Claude compatibility layer: keep existing ~/.claude workflows functional,
+# but source canonical rails from ~/.mosaic.
+link_tree_files "$MOSAIC_HOME/guides" "$HOME/.claude/agent-guides"
+link_tree_files "$MOSAIC_HOME/rails/git" "$HOME/.claude/scripts/git"
+link_tree_files "$MOSAIC_HOME/rails/codex" "$HOME/.claude/scripts/codex"
+link_tree_files "$MOSAIC_HOME/rails/bootstrap" "$HOME/.claude/scripts/bootstrap"
+link_tree_files "$MOSAIC_HOME/templates/agent" "$HOME/.claude/templates"
+
+for qa_script in \
+  debug-hook.sh \
+  qa-hook-handler.sh \
+  qa-hook-stdin.sh \
+  qa-hook-wrapper.sh \
+  qa-queue-monitor.sh \
+  remediation-hook-handler.sh; do
+  src="$MOSAIC_HOME/rails/qa/$qa_script"
+  [[ -f "$src" ]] || continue
+  link_file "$src" "$HOME/.claude/scripts/$qa_script"
+done
+
+echo "[mosaic-link] Runtime compatibility assets linked"
+echo "[mosaic-link] Canonical source: $MOSAIC_HOME"