feat(docx): space paragraphs and size table rows

[andiwand]

🤖 Generated with Claude Code

A .docx was rendered with none of the spacing Word gives it: paragraphs sat
line against line and every table row collapsed onto its text. The renderer was
not at fault — html/document_style.cpp has emitted margin-top/bottom,
line-height and a row height all along. The docx style reader simply never
produced them: resolve_paragraph_style_ read w:jc and w:ind and nothing
else, and resolve_table_row_style_ was an empty // TODO.

What it reads now

• w:spacing → w:before/w:after as the paragraph's top and bottom
  margin, w:line as its line height, honouring w:lineRule: auto is
  240ths of a line and becomes a percentage, atLeast/exact are twips. A
  w:beforeAutospacing/w:afterAutospacing flag suppresses the value it
  shadows rather than applying a number Word would have ignored.
• w:trPr/w:trHeight → the table row's height, skipped for
  w:hRule="auto". CSS gives a <tr> height minimum semantics, which is what
  atLeast means (Word omits the rule for it); an exact cap is not
  expressible on a row and is not attempted.

What had to come with it

Both alone would have been a net regression, so this PR also carries:

• w:contextualSpacing — Word drops the spacing towards a neighbouring
  paragraph of the same style, which is what keeps a list tight. Without it
  every ListParagraph list gained 8pt between items. It is decided per
  paragraph rather than per style, so partial_paragraph_style compares the
  w:pStyle of the adjacent w:p siblings and zeroes the margin it applies
  to; Style carries the flag beside its ResolvedStyle so an inherited one
  is seen.
• w:tblStyle resolution — a table style carries the paragraph and text
  properties of everything in the table (TableGrid sets w:spacing w:after="0"). Without it the doc defaults loosened every cell. A table now
  resolves its style reference the way a paragraph resolves w:pStyle and
  contributes the whole resolved style, which the existing element-tree cascade
  carries down. Its conditional formats (w:tblStylePr) are still ignored.

ooxml_util gains read_on_off_attribute for ST_OnOff in both its shapes.

Verification

• Seven new cases in ooxml_text_style_test.cpp, inline XML, no fixtures.
• Full suite green: 936 passed, the 8 usual skips.
• Every .docx in the test data was rendered and compared against the previous
  reference output in a browser. Tables stay tight, lists stay tight, headings
  gain their real space-before, and sample1.docx's calendar table now renders
  right-aligned grey day numbers in tall rows — what Word shows, and what the
  old output missed entirely.

Reference output

Regenerated and pushed; both pins advanced. 16 files in odr-public, 3 in
odr-private, all docx/*/document.html — no other format moved.

[chatgpt-codex-connector]

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