Pure model layer for x-calendar. No DOM, no side effects — every
function is a value transform. Dates flow as ISO "YYYY-MM-DD" strings;
the canonical model holds only value-comparable data (strings, keywords,
numbers, sets) so the render change-guard can compare it with `not=`.
UTC date math lives in baredom.utils.dates.

DOM + lifecycle layer for x-calendar — a standalone, always-visible
inline month calendar. Pure date/model logic lives in
baredom.components.x-calendar.model and baredom.utils.dates; this
namespace only performs DOM side effects.

Pure model layer for x-code — a code-display component with an in-house,
regex-based syntax tokenizer.

No DOM, no side effects. Every function here is a plain data transform and
is exercised directly by model_test.cljs with sparse inputs.

The tokenizer is deliberately lightweight. It covers js / json / css / html
only and degrades any other language to plain text. It is a highlighter,
not a parser: it does not track nested languages, and a handful of
context-sensitive cases are knowingly imperfect (see docs/x-code.md).

DOM + lifecycle layer for x-code — a code-display component.

The component is stateless: DOM = f(attributes, properties). Source code is
read from the element's light-DOM textContent (or the `code` property /
attribute), tokenized by the pure model layer, and rendered escaped into
the shadow `<code>`. A MutationObserver re-renders when the light-DOM text
changes. The expand/collapse state lives in the observed `expanded`
attribute, so it too is a value, never a mutable field.

Instance fields hold only the refs map, the cached model, the
MutationObserver, and the `code` property override.

Pure model layer for x-split-pane — a resizable two-panel layout.

No DOM, no side effects. Every function here is a plain data transform
and is exercised directly by model_test.cljs with sparse inputs.

DOM + lifecycle layer for x-split-pane.

A resizable two-panel layout. The divider position is a percentage held
in the `position` attribute — the single source of truth. A drag or
keyboard step writes that attribute; the render pipeline reads it back
and applies `flex-basis`. The element is stateless: instance fields hold
only the refs map, the cached model, and a transient dragging flag.

Pure functions for the x-welcome-tour-step child element.
This component is a passive data holder — the parent orchestrator
reads its attributes and renders the tour UI.

Passive child element for x-welcome-tour.
Holds step configuration as attributes and provides a default slot
for rich content. The parent orchestrator reads these attributes
and renders the tour UI — this element never renders visibly itself.

Pure functions for the x-welcome-tour orchestrator component.
Positioning, cutout geometry, connector path computation, and
attribute normalisation — no DOM or side effects.

Orchestrator for the welcome tour overlay.
Manages the SVG spotlight backdrop, popover positioning, step
navigation, connector rendering, focus trap, and keyboard/scroll/resize
handling. The host element is invisible — all visible UI lives in a
portal layer created via the shared overlay utility.