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, 0 insertions, 17 deletions

diff --git a/internal/render/render_test.go b/internal/render/render_test.go
index 00c8a85..dd177bb 100644
--- a/internal/render/render_test.go
+++ b/internal/render/render_test.go
@@ -7,23 +7,6 @@ import (
 	"github.com/lukaszkasprzak/lectio/internal/liturgy"
 )
 
-func TestGatherBTDedup(t *testing.T) {
-	sec := liturgy.Section{
-		Heading:    "Psalm (Ps 1)",
-		Paragraphs: [][]string{{"stanza one"}, {"refrain"}, {"stanza two"}, {"refrain"}},
-	}
-	_, blocks := GatherVersion("bt", sec, "new", "pl")
-	n := 0
-	for _, b := range blocks {
-		if b == "refrain" {
-			n++
-		}
-	}
-	if n != 1 {
-		t.Errorf("refrain appears %d times, want 1 (deduped)", n)
-	}
-}
-
 func TestGatherBible(t *testing.T) {
 	// Offline sections carry the English-canonical lookup reference in Ref; the
 	// display citation stays in the reader's sigla dialect.