feat(templates): let the column-flow presets take a runtime module

[DemchaAV]

Why

CvTemplates.modular() is the list a CV builder offers when the CV is assembled at
runtime, and every template on it was single-column. The three column-flow presets —
SidebarPortrait, MonogramSidebar, MintEditorial — had everything the promise needs
after the leftover-tail and slot-heading work, but nothing said so, so a caller building
a CV from data could not offer a two-column design at all.

What

The three declare ModularCvTemplate; the list goes from seven templates to ten. They
earn it through their own renderers rather than the shared dispatcher: a module is
lowered by SectionRouter to the shape its slot draws and drawn by that slot, or by the
leftover tail under the author's heading — which is why it already comes out in the
preset's style.

Rather than guess what the contract needed, I declared the interface and let
ModularCvTemplateFidelityTest answer. It found six failures, and the split is the
interesting part: four were the harness, one was over-specification, and two
were real.

The real one. Sidebar Portrait and Monogram Sidebar drew a grouped skills section as
one flat run of every skill in the CV. The shipped fixture has thirty-two skills under six
category names and not one of those names reached a page, so a module whose only label was
its group name arrived anonymous. Each group is headed by its own name now — which is also
easier to read than twelve-plus unlabelled lines.

That label is skipped when it would repeat the heading the block just drew: a module whose
items carry no bodies is lowered into a single group named after the module itself, so the
sidebar would otherwise print the section's title twice in a row. The comparison is on the
titles as written, not through SectionLookup.normalize — that strips every character
outside [a-z0-9] because it matches English keyword lists, so two Cyrillic titles both
reduce to "" and every non-Latin CV would lose the label instead. The gate caught that
one on the way in. MintEditorial's own bars/index dedup went the same way; it was safe
only because one side of it is always a Latin literal.

kit() returns the canonical kit for all three, and says why: a kit styles the bodies
a preset routes through SectionDispatcher, and these route none. SectionDispatcher
also resets the host's spacing and padding, which would fight a column layout, and
CvRenderKit has no way to say which of a two-column preset's body styles it is drawing.

Tests

ModularCvTemplateFidelityTest gained three corrections, all of which weaken nothing:

• Item assertions dropped case but not letter-spacing while the heading assertion dropped
  both, so a preset that letter-spaces an entry title failed for its typography rather
  than for losing anything. Items are normalised the same way headings always were — and
  per paragraph, so a match has to live inside one node rather than being assembled
  out of two that happen to adjoin, which whole-page squashing would have allowed.
• It required the canonical "Java 21, Kotlin" join for a skills group. That is a
  rendering style, not a promise — a preset drawing bars or a list shows both skills and
  failed anyway. It asserts the group's name and its skills in order, as a subsequence,
  which keeps the grouping and ordering the join carried.
• Its per-kind markers were prefixes of one another: Item ENTRIES lives inside
  Item ENTRIES DATED, so a template could drop two of the six kinds outright and stay
  green. Pre-existing, and this change re-derived every one of those assertions, so it is
  fixed here.

SlotHeadingFidelityTest gains the case the fidelity fixtures never reach — a skills
module whose items carry no bodies, which is the natural runtime shape for a flat list.
Both presets were sabotaged to confirm it goes red without the dedup.

groupTokens reads SkillGroup.skills() instead of splitting skillsInline() back apart
on commas, which cut a skill carrying a comma of its own in half.

Full reactor gate green. Four baselines re-recorded (sidebar_portrait ×2,
monogram_sidebar ×2), the twelve visual.approve rewrote as collateral reverted, two
committed previews refreshed. The pixel gate passed at every step without being told
anything — measured at budget 0, the grouping moves 3,515 + 11,923 px on Sidebar Portrait
and 1,019 + 9,687 on Monogram Sidebar, all well under the 50,000 the budget allows for
cross-platform font drift.

docs/templates/v2-layered/using-templates.md still told readers these three were kept
off the modular list because they rename headings — which stopped being true when every
slot started printing the author's title. That paragraph, the single-main-column claim it
repeated, and the CvRenderKit paragraph are updated; the same falsified sentence in
ModularCvTemplate's own Javadoc is corrected too.