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, 3 insertions, 2 deletions

diff --git a/internal/cli/liturgy.go b/internal/cli/liturgy.go
index aa3f97e..07a87bc 100644
--- a/internal/cli/liturgy.go
+++ b/internal/cli/liturgy.go
@@ -15,8 +15,9 @@ import (
 )
 
 // runLiturgy prints the computed liturgical day for date (default today) using
-// the offline calendar engine, and exits. It is the engine's demo/validation
-// surface; the daily-readings paths still use the scraper.
+// the offline calendar engine, and exits. It shows the day's identity and
+// resolved reading citations; the daily-readings paths render the same offline
+// engine's readings as full text.
 func runLiturgy(cfg config.Config, date string, stdout, stderr io.Writer) int {
 	if date == "" {
 		date = today()