v0.7.4

Added

• keyboard plugin (global) — exposes the soft (on-screen) keyboard's
  geometry on :root: --live-keyboard-open (1/0), --live-keyboard-height,
  --live-keyboard-width, and --live-keyboard-x / -y / -right / -bottom
  (px, client coordinates), so layout can reflow around the keyboard with pure
  CSS — padding-block-end: calc(var(--live-keyboard-height) * 1px). Reads exact
  geometry from the VirtualKeyboard API on Chromium/Android (it sets
  navigator.virtualKeyboard.overlaysContent = true while bound — so the
  keyboard overlays content instead of resizing the viewport — and restores it on
  dispose), and falls back to inferring the height from visualViewport shrink on
  iOS/Safari (approximate: a pinch-zoom can read as a keyboard). Seeds zeros where
  neither API is available. (#6)
• meta plugin (global) — writes every <meta name|property + content> on
  the page as a write-once --const-meta-<slug> (the slug lowercases the name and
  collapses runs of non-alphanumerics to a single dash): --const-meta-theme-color,
  --const-meta-og-image, --const-meta-color-scheme, etc. — so CSS can read page
  metadata directly (background: var(--const-meta-theme-color),
  background-image: url(var(--const-meta-og-image))). First match wins per name,
  and a media-conditional meta is skipped when its query doesn't currently match,
  so the active theme-color variant is the one written. Read once at bind on the
  const cadence, so meta tags swapped in by a framework after bind aren't
  tracked. (#7)

Both are tree-shakeable opt-in plugins — import from prop-for-that/plugins, or
let auto load them on demand via data-props-for.