1.0.1

Added

• Relative subplot sizes through column_widths and row_heights, and per-cell right y
  axes through specs: [[{secondary_y: true}]]. Trace placement, trace updates and y-axis
  updates accept secondary_y; existing primary axis numbering is preserved.
• Animation frames through Figure.new(frames:), add_frame and frames=, with validation
  of partial trace/layout updates and inclusion in JSON output. HTML and notebook output
  register frames and start playback; to_html and write_html accept auto_play and
  animation_opts.
• Runnable examples for secondary axes and animation.

Fixed

• Require json >= 2.9 to avoid the older script_safe bug that corrupts characters such
  as 瀨 and 倩 in chart labels and JSON output.
• Reject negative, non-finite and out-of-range subplot spacing instead of silently
  overlapping or collapsing cells; reject invalid row/column counts before calculating defaults.