feat(daemon): add GET /status endpoint (bd-148)

- Add OpStatus operation and StatusResponse type to RPC protocol
- Add workspacePath and dbPath fields to Server struct
- Implement handleStatus() handler with daemon metadata
- Track last activity time with atomic.Value
- Add client.Status() method
- Check for exclusive locks via ShouldSkipDatabase()
- Update all test files to use new NewServer signature
- Add comprehensive status endpoint test

Closes bd-148

internal/rpc/client.go

@@ -179,6 +179,21 @@ func (c *Client) Ping() error {
 	return nil
 }
 
+// Status retrieves daemon status metadata
+func (c *Client) Status() (*StatusResponse, error) {
+	resp, err := c.Execute(OpStatus, nil)
+	if err != nil {
+		return nil, err
+	}
+
+	var status StatusResponse
+	if err := json.Unmarshal(resp.Data, &status); err != nil {
+		return nil, fmt.Errorf("failed to unmarshal status response: %w", err)
+	}
+
+	return &status, nil
+}
+
 // Health sends a health check request to verify the daemon is healthy
 func (c *Client) Health() (*HealthResponse, error) {
 	resp, err := c.Execute(OpHealth, nil)