refactor: remove the niedziela/missalemeum scrapers, bt, traditional_lang

The daily view now computes entirely offline (previous commit), so retire the
network path and everything that served it:

- Delete internal/tradlit (missalemeum) and the niedziela scraper from
  internal/liturgy (fetch/store/parse + fixtures); keep Section, DayInfo and
  ExtractCitation.
- Remove the "bt" version everywhere (render gatherBT + branches, config,
  i18n, web form, TUI) and bible.ToEnglishRef (Polish citation converter).
  A legacy config carrying "bt" migrates to "wuj" on load (config.migrateBT).
- Remove the traditional_lang config field and the -g/--lang flag from all
  three binaries.
- Drop the now-dead flags -R/--refresh, -o/--offline, -u/--update,
  -C/--clean and the harvest/clean commands.
- New defaults: versions = wuj,vul,grb,drb; default_version = vul.

Update the README (offline-by-design, no harvest/update), help text, and
stale niedziela/bt doc comments. Tests updated for the offline reality;
go test ./... and go vet ./... are clean, all three binaries build and run
offline (OF + EF, compare, web).

1 files changed, 16 insertions, 9 deletions

diff --git a/internal/export/export_test.go b/internal/export/export_test.go
index 7f1c68d..5adf7d4 100644
--- a/internal/export/export_test.go
+++ b/internal/export/export_test.go
@@ -8,30 +8,37 @@ import (
 	"github.com/lukaszkasprzak/lectio/internal/liturgy"
 )
 
+// sampleSecs builds a reading section the offline way: the English-canonical
+// lookup reference lives in Ref, the display citation stays in the reader's
+// sigla dialect. render.GatherVersion resolves Ref against a real embedded
+// corpus, so the exported document carries actual verse text.
 func sampleSecs() []liturgy.Section {
 	return []liturgy.Section{{
-		Heading:    "Ewangelia (Mt 13, 1-9)",
-		Citation:   "Mt 13, 1-9",
-		PartID:     "ewangelia",
-		Paragraphs: [][]string{{"Owego dnia Jezus wyszedł z domu i usiadł nad jeziorem."}},
+		Heading:  "Ewangelia",
+		Citation: "J 20, 1. 11-18",
+		Ref:      "John 20:1,11-18",
+		PartID:   "ewangelia",
 	}}
 }
 
 func TestMarkdownAndText(t *testing.T) {
 	info := liturgy.DayInfo{Name: "Środa XV tygodnia", Colour: "green"}
-	md := Markdown("2026-07-22", info, sampleSecs(), "bt", "new", "en")
-	if !strings.Contains(md, "# Środa") || !strings.Contains(md, "## Gospel") || !strings.Contains(md, "Jezus wyszedł") {
+	// vul -> Vulgate Latin verse text, versified ("20:1  Una autem sabbati,
+	// Maria Magdalene ...").
+	md := Markdown("2026-07-22", info, sampleSecs(), "vul", "new", "en")
+	if !strings.Contains(md, "# Środa") || !strings.Contains(md, "## Gospel") ||
+		!strings.Contains(md, "20:1") || !strings.Contains(md, "Maria Magdalene") {
 		t.Errorf("markdown:\n%s", md)
 	}
-	txt := Text("2026-07-22", info, sampleSecs(), "bt", "new", "en")
-	if !strings.Contains(txt, "Jezus wyszedł") || !strings.Contains(txt, "Gospel") {
+	txt := Text("2026-07-22", info, sampleSecs(), "vul", "new", "en")
+	if !strings.Contains(txt, "Maria Magdalene") || !strings.Contains(txt, "Gospel") {
 		t.Errorf("text:\n%s", txt)
 	}
 }
 
 func TestReadingsPDF(t *testing.T) {
 	info := liturgy.DayInfo{Name: "Środa XV tygodnia"}
-	pdf, err := ReadingsPDF("2026-07-22", info, sampleSecs(), "bt", "new", "en")
+	pdf, err := ReadingsPDF("2026-07-22", info, sampleSecs(), "vul", "new", "en")
 	if err != nil {
 		t.Fatal(err)
 	}