web: horizontal/vertical/interlinear display modes + web_display config

Adds a display-layout option to lectio-web alongside the existing colour
themes:

- config: WebDisplay field (toml web_display), default "horizontal",
  normalized on load via the new exported config.NormalizeDisplay
  (unknown -> "horizontal", same lenient style as the other web_* fields).
- render: extracts the citation/ToEnglishRef resolution shared by
  GatherVersion into an unexported resolveRef helper (GatherVersion's
  signature/behavior unchanged) and adds GatherVerses(version, sec,
  lectionary) returning raw bible.Verse structs plus a versified flag, for
  column/interlinear alignment.
- web/render: RenderReadings gains a display parameter. "horizontal" is
  the original stacked layout, byte-for-byte the same code path as
  before. "vertical" reuses the same per-version column data in a
  .display-vertical/.vcol grid (the CLI compare view, browser-side).
  "interlinear" maps versions through render.OfflineVersions' pl->wuj
  substitution (pl has no verse numbers), gathers GatherVerses per
  version, and interleaves them by chapter:verse into .ilverse/.illine
  blocks (ordered union of keys, first versified version's order first).
- server: adds a display <select> to the top bar wired into the existing
  #controls HTMX form; a resolveQuery(cfg, r) helper replaces the
  duplicated date/lectionary/all/versions(+now display) resolution in
  indexHandler and readingsHandler.
- fold-in from the B2 review: indexHandler now populates indexData.Lookup
  via a shared renderLookup(ref, versions) helper (also used by
  lookupHandler), so a bookmarked "/?ref=...&v=..." link shows its
  lookup result instead of an empty pane.
- base.css: layout-only rules for the two new modes (no colours; themes
  stay colour-only).

go test ./..., go vet ./..., gofmt clean; go build ./cmd/lectio-web ok.

1 files changed, 29 insertions, 0 deletions

diff --git a/internal/web/templates/readings-vertical.html b/internal/web/templates/readings-vertical.html
new file mode 100644
index 0000000..08f526d
--- /dev/null
+++ b/internal/web/templates/readings-vertical.html
@@ -0,0 +1,29 @@
+{{/* readings-vertical.html renders the reading pane fragment in vertical
+     (side-by-side columns) layout: one <section> per liturgy.Section, all
+     requested versions laid out in a .display-vertical grid, one .vcol per
+     version -- the browser equivalent of the CLI `compare` view. Data and
+     role classes (heading/citation/version-label/vnum/refrain) match
+     readings.html so theme CSS restyles both identically; base.css owns
+     the .display-vertical/.vcol layout. */}}
+{{range .}}
+<section class="reading-section" data-part="{{.PartID}}">
+  <h2 class="heading">{{.Heading}}</h2>
+  {{if .Subtitle}}<p class="citation">{{.Subtitle}}</p>{{end}}
+  <div class="display-vertical">
+    {{range .Columns}}
+    <div class="vcol">
+      <h3 class="version-label">{{.Label}}</h3>
+      {{range .Blocks}}
+        {{if .Refrain}}
+      <p class="block refrain">{{.Text}}</p>
+        {{else if .VNum}}
+      <p class="block verse"><span class="vnum">{{.VNum}}</span> {{.Text}}</p>
+        {{else}}
+      <p class="block">{{.Text}}</p>
+        {{end}}
+      {{end}}
+    </div>
+    {{end}}
+  </div>
+</section>
+{{end}}