feat(identity): sync.sh and syncro.md read from identity.json

Phase 2 migration complete:

sync.sh:
- Read Python command from identity.json first (.python.command)
- Fall back to auto-detection for legacy machines
- Eliminates per-session detection overhead

syncro.md:
- Read Ollama endpoint from identity.json (.ollama.endpoint // .ollama.fallback)
- Read Python command from identity.json (.python.command)
- Both sections have legacy fallbacks with detection
- Eliminates 2-second curl probe on every write operation
- Updated day-of-week verification code example
- Updated Ollama draft call section

Impact: All scripts now read machine-specific config from identity.json
(populated by migrate-identity.sh). Faster, explicit, offline-safe.

.claude/scripts/sync.sh

@@ -116,18 +116,26 @@ cd "$REPO_ROOT"
 
 echo -e "${GREEN}[OK]${NC} Working directory: $(pwd)"
 
-# Detect Python interpreter — verify it actually runs (Windows Store stub passes command -v but fails to execute)
+# Detect Python interpreter — read from identity.json first, fall back to detection
 PYTHON=""
-for candidate in py python3 python; do
-    if command -v "$candidate" >/dev/null 2>&1; then
-        if "$candidate" -c "import sys; sys.exit(0)" >/dev/null 2>&1; then
-            PYTHON="$candidate"
-            break
-        fi
-    fi
-done
+if [ -f ".claude/identity.json" ] && command -v jq >/dev/null 2>&1; then
+    PYTHON=$(jq -r '.python.command // empty' ".claude/identity.json" 2>/dev/null)
+fi
+
+# Fallback: auto-detect if not in identity.json
 if [ -z "$PYTHON" ]; then
-    echo -e "${RED}[ERROR]${NC} No Python interpreter found (tried: py, python3, python)"
+    for candidate in py python3 python; do
+        if command -v "$candidate" >/dev/null 2>&1; then
+            if "$candidate" -c "import sys; sys.exit(0)" >/dev/null 2>&1; then
+                PYTHON="$candidate"
+                break
+            fi
+        fi
+    done
+fi
+
+if [ -z "$PYTHON" ]; then
+    echo -e "${RED}[ERROR]${NC} No Python interpreter found. Run .claude/scripts/migrate-identity.sh to populate identity.json."
     exit 1
 fi