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, 40 insertions, 0 deletions

diff --git a/internal/config/config_test.go b/internal/config/config_test.go
index 9b72bc7..9ca311b 100644
--- a/internal/config/config_test.go
+++ b/internal/config/config_test.go
@@ -59,6 +59,46 @@ func TestWebLoadsFromSeed(t *testing.T) {
 	if cfg.WebPort != 0 {
 		t.Errorf("WebPort from seed wrong: got %d, want 0", cfg.WebPort)
 	}
+	if cfg.WebDisplay != "horizontal" {
+		t.Errorf("WebDisplay from seed wrong: got %q, want %q", cfg.WebDisplay, "horizontal")
+	}
+}
+
+func TestWebDisplayDefault(t *testing.T) {
+	def := Default()
+	if def.WebDisplay != "horizontal" {
+		t.Errorf("WebDisplay default wrong: got %q, want %q", def.WebDisplay, "horizontal")
+	}
+}
+
+func TestWebDisplayLoadsSetting(t *testing.T) {
+	dir := t.TempDir()
+	t.Setenv("XDG_CONFIG_HOME", dir)
+	os.MkdirAll(filepath.Join(dir, "lectio"), 0o755)
+	os.WriteFile(filepath.Join(dir, "lectio", "config.toml"),
+		[]byte("web_display = \"vertical\"\n"), 0o644)
+	cfg, err := Load()
+	if err != nil {
+		t.Fatal(err)
+	}
+	if cfg.WebDisplay != "vertical" {
+		t.Errorf("WebDisplay = %q, want %q", cfg.WebDisplay, "vertical")
+	}
+}
+
+func TestWebDisplayNormalizesUnknown(t *testing.T) {
+	dir := t.TempDir()
+	t.Setenv("XDG_CONFIG_HOME", dir)
+	os.MkdirAll(filepath.Join(dir, "lectio"), 0o755)
+	os.WriteFile(filepath.Join(dir, "lectio", "config.toml"),
+		[]byte("web_display = \"bogus\"\n"), 0o644)
+	cfg, err := Load()
+	if err != nil {
+		t.Fatal(err)
+	}
+	if cfg.WebDisplay != "horizontal" {
+		t.Errorf("WebDisplay = %q, want %q (normalized from bogus)", cfg.WebDisplay, "horizontal")
+	}
 }
 
 func TestPartShown(t *testing.T) {