fix(docx): take a line's upward pull off the line above it when no space above can give it

[DemchaAV]

Why

CobaltRota's masthead stood about 7pt low in Word, and the whole rota under it with it.

• Its lockup is two lines in a table cell: a 21pt wordmark, and a subtitle pulled 6.5pt up under it by a negative top margin.
• Since fix(docx): take a block's upward pull out of the space above it, and hold a row's padding at the top of its column #793, a paragraph's negative top edge comes out of the space owed above it. In a cell under another line there is none, so the pull was dropped.

What changed

• standsIntoTheSpaceAbove. Where the space above still falls short after the pull is netted, a paragraph takes the rest in two steps.
  • takeFromTheLineAbove. It takes from the foot of the line written just before. That must be the Word paragraph writeParagraph wrote last (lastWrittenNode / lastWrittenParagraph), still lastBodyParagraph, and on the page the pulled paragraph starts on. It must also be one exact line of text, not one of a stack, with no space below it and no run shaded or underlined: shading fills the line, and an underline is drawn below the letters.
    • The line is written shorter by as much as its letters leave room below them where Word draws them, DocxStackedLines.INK_MARGIN clear. That room is read off Word's geometry: its baseline a fifth of the line above the foot, raised by the runs' written w:position, the letters' reach taken unseated from DocxInk.
    • Its runs are lowered by four fifths of that, as Word would raise its text with the baseline of a shorter exact line.
  • riseInsideItsOwnLine. It takes what is left from the top of the pulled line, as riseIntoItsLine does for a container's first line: a DocxStackedLines.Line limited by the room above its letters, seated where the page sets it.
• A table, a page break or a new cell clears lastBodyParagraph, so the line above is never one across them. A line holding a picture has no ink DocxInk can read, so it is left whole.
• Docs. CHANGELOG.md and the negative-edge paragraph of docs/recipes/docx-export.md are updated.

Verification

• Full reactor gate: ./mvnw -B -ntp clean verify -pl :graph-compose-core,:graph-compose-render-pdf,:graph-compose-render-docx,:graph-compose-render-pptx,:graph-compose-templates,:graph-compose-testing,:graph-compose-qa,:graph-compose-coverage -am gives BUILD SUCCESS (1791 + 127 tests).
  • After install, examples run 93 green.
  • The knowledge checks and extract-api --check pass.
  • render-docx runs 714 tests.
• DocxSpaceAboveTest (new):
  • A subtitle pulled 2pt up under a 21pt wordmark in a row's cell: the wordmark's line is 2pt shorter, its text lowered 3 half points, and the subtitle's line whole.
  • A pull deeper than the letters above leave room for: the line above gives some, and the pulled line the rest.
  • A 3.5pt pull lowers the wordmark's text 6 half points, pinning the four fifths (three quarters would round to 5).
  • A line above whose text is shaded, or underlined, is left whole: its line and position equal a render without the pull.
• Each step fails its own test when reverted: the take from the line above, the rise inside the pulled line, the shading and underline guards, and the four-fifths lowering (0.75 gives 5 half points, not 6).
• Template corpus (62 documents), against 2.5-dev: only CobaltRota changes.
  • Its median drift falls from 8.9pt to 2.4 in Word and in LibreOffice.
  • Its lines more than 2pt off fall from 65 to 45 in Word, and from 62 to 47 in LibreOffice.
  • It stays one page.
  • On Word's screen at 300%, the wordmark's Q and the subtitle show whole.

Known limits

• A pull the resumed space of a layered row would have absorbed is taken from the line above first, so a little of it can go unwritten.
• A paragraph written a second time in a different context is not remembered as the container first line is.
• CobaltRota's remaining drift is its outlined chips (1.1pt a row) and its group icons, anchored a row low.

Lane: shared-engine (render-docx). No public API change.