feat(identity): read claudetools_root from identity.json

- Updated sync.sh to read claudetools_root from identity.json
- Updated syncro.md skill to use identity.json for repo path
- Updated CLAUDE.md onboarding to include claudetools_root field
- Eliminates cross-architecture path detection issues
- Fallback to git rev-parse for legacy machines

Each machine sets claudetools_root during onboarding, just like vault_path.

.claude/scripts/sync.sh

@@ -54,25 +54,41 @@ TIMESTAMP=$(date "+%Y-%m-%d %H:%M:%S")
 echo -e "${GREEN}[OK]${NC} Starting ClaudeTools sync from $MACHINE at $TIMESTAMP"
 
 # Navigate to ClaudeTools directory
-# First check: are we already in the repo (or a subdirectory of it)?
-REPO_ROOT=$(git rev-parse --show-toplevel 2>/dev/null || true)
-if [ -n "$REPO_ROOT" ]; then
-    cd "$REPO_ROOT"
-else
-    # Fall back to known candidate paths
+# Read from identity.json (machine-specific, set during onboarding)
+IDENTITY_PATH=""
+for candidate in "$HOME/.claude/identity.json" ".claude/identity.json"; do
+    if [ -f "$candidate" ]; then
+        IDENTITY_PATH="$candidate"
+        break
+    fi
+done
+
+if [ -n "$IDENTITY_PATH" ] && command -v jq >/dev/null 2>&1; then
+    REPO_ROOT=$(jq -r '.claudetools_root // empty' "$IDENTITY_PATH" 2>/dev/null)
+fi
+
+# Fallback: git detection if identity.json doesn't have claudetools_root yet
+if [ -z "$REPO_ROOT" ]; then
+    REPO_ROOT=$(git rev-parse --show-toplevel 2>/dev/null || true)
+fi
+
+# Last resort: hardcoded paths (legacy machines)
+if [ -z "$REPO_ROOT" ]; then
     for candidate in "$HOME/ClaudeTools" "/d/ClaudeTools" "D:/ClaudeTools" "/d/claudetools" "D:/claudetools" "C:/claudetools" "/c/claudetools"; do
         if [ -d "$candidate/.git" ]; then
-            cd "$candidate"
+            REPO_ROOT="$candidate"
             break
         fi
     done
 fi
 
-if [ ! -d ".git" ]; then
-    echo -e "${RED}[ERROR]${NC} Not in a git working tree"
+if [ -z "$REPO_ROOT" ] || [ ! -d "$REPO_ROOT/.git" ]; then
+    echo -e "${RED}[ERROR]${NC} Cannot locate ClaudeTools repo. Add 'claudetools_root' to identity.json"
     exit 1
 fi
 
+cd "$REPO_ROOT"
+
 echo -e "${GREEN}[OK]${NC} Working directory: $(pwd)"
 
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