v2.4.4

PATCH release. Lifts the visual quality of both the figures AI produces
and the dashboard chrome that surrounds them to match a published
Research-OS reference deliverable (cream background, italic serif
titles, muted CVD-safe accent palette, value-labels-above-bars, clean
spines, generous whitespace). Also turns the loose "look at the
rendered figure" guidance into a mandatory render → view → v2 loop so
the AI can no longer ship a figure it never opened.

Added

• research_os.tools.actions.viz.style — new module exporting
  the Research-OS publication style preset for matplotlib:
  • apply_research_os_style(destination=..., palette=...) —
    one call sets rcParams (cream bg, serif typography, dropped
    spines, dotted horizontal grid, constrained_layout on,
    300 dpi save) and returns a context dict with the destination
    figsize + palette so the AI's first render lands close to
    publication-ready. Destinations: single_col / two_col /
    full_width / slide / slide_half / dashboard /
    dashboard_tile / poster.
  • RO_PALETTE — five muted CVD-safe accents
    (navy #1F4D7A, olive #9B7E2D, forest #3F6049, oxblood
    #9B3737, mustard #C3A14E) plus a diverging emphasis pair
    (oxblood / forest) and a neutral chrome set
    (cream / warm-dark / muted / hairline).
  • DESTINATION_FIGSIZES — pre-tuned (width, height) for every
    destination so the AI doesn't pick a 6×4 default that crops at
    print size.
  • label_bars_above(ax, bars, unit="ms") — italic value labels
    floating 2 % above each bar, matching the reference figure
    aesthetic (467 ms, 128 ms, …). Reserves headroom so the
    label doesn't crash into the next bar in a stacked chart.
  • label_diverging_bars(ax, bars, values) — signed delta labels
    coloured forest (positive) / oxblood (negative) for the
    diverging-bar comparison panel.
  • polish_axes(ax) — re-asserts top + right spine off and
    dotted horizontal grid on a specific axes after the AI built
    the chart.
  • apply_suptitle(fig, title, subtitle=...) — italic serif
    suptitle + smaller subtitle line, positioned to never overlap
    constrained_layout.
  • Graceful import: when matplotlib isn't installed, the module
    still imports and returns applied=False from
    apply_research_os_style instead of raising.
• first_render_spacing_discipline: block in
  visualization/figure_guidelines — a 9-item upfront discipline
  (pick destination, leave y-margin for value labels, plan legend
  placement, decide tick rotation, reserve suptitle headroom) so the
  FIRST render doesn't need a v2 to fix spacing. Calls out the
  matplotlib tight_layout() ↔ constrained_layout conflict.
• visually_verify_render step in
  visualization/visualization_workflow — the workflow's
  counterpart to the strengthened pre_publish_self_review step in
  figure_guidelines. Both protocols now teach the same mandatory
  render → open the PNG → check overlap / clipping / legend
  placement / palette cohesion → write v2 if anything fails → only
  ship v_final loop.
• Research-OS accent palette in audit_color_palette — the
  five RO_PALETTE accents + the neutral chrome colours are now in
  the allowed-palette set, so dashboards built from the new
  scaffold and figures generated through apply_research_os_style
  no longer trip the out-of-palette warning.

Changed

• synthesis/scaffold._DASHBOARD_HTML — full CSS rewrite to
  match the reference figure aesthetic. Cream background, two-font
  stack (EB Garamond serif for titles + figure captions, Inter sans
  for body), italic serif h1 / h2 / h3 / table headers, muted
  accent palette as CSS variables (--accent navy, --accent-gold
  olive, --accent-green forest, --accent-red oxblood,
  --accent-mustard), hairline rule colour for separators,
  near-white cards on cream, italic figcaption for figure
  interpretation, print-friendly fallback retained. Adds an
  .eyebrow line and a .lead paragraph class in the hero so the
  TL;DR has room to breathe.
• visualization/figure_guidelines (v2.0.0 → v2.4.4) — adds the
  research_os_style_preset reference block, the
  first_render_spacing_discipline rules, the new set_up_canvas
  step (call apply_research_os_style BEFORE writing the chart
  code), and rewrites pre_publish_self_review into the mandatory
  open-the-PNG view loop with explicit sys_file_read filepath=...
  instructions and a 14-item OBSERVATION checklist that the human
  eye must verify against the rendered pixels.
• visualization/visualization_workflow (v2.0.0 → v2.4.4) —
  inserts visually_verify_render after build_each_figure so the
  on-demand figure workflow inherits the same loop. Updates
  build_each_figure to mention apply_research_os_style + the
  spacing discipline.
• synthesis/synthesis_dashboard (v2.4.3 → v2.4.4) — adds a
  "visual cohesion with the figures" principle pointing at
  apply_research_os_style(); bumps version.

Test gate

• tests/unit/test_viz_style.py — new file covering the style
  preset surface (palette has 5+ entries, DESTINATION_FIGSIZES has
  the expected destinations, apply_research_os_style returns the
  context dict, helpers no-op safely without matplotlib bars).
• tests/unit/test_v244_dashboard_style.py — new file covering
  the dashboard CSS rewrite (cream bg + accent palette present in
  scaffold, section IDs preserved, print stylesheet retained, new
  accent palette passes audit_color_palette without warnings,
  protocol YAMLs updated with the new spacing + view loop language).
• preflight passes · pytest passes · ruff clean.

Not behaviour change for existing projects

• Pre-v2.4.4 dashboards on disk are untouched — the new CSS only
  applies to scaffolds created after upgrading. Re-scaffold with
  tool_synthesis_scaffold(kind='dashboard', overwrite=true) to
  adopt the new style.
• The style preset is opt-in. Plotting scripts that don't import
  apply_research_os_style continue to render with matplotlib
  defaults. The figure_guidelines protocol recommends adopting
  the preset for visual cohesion with the dashboard, but doesn't
  reject figures that depart from it (journal templates win).

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