test(bible): skip corpus-dependent tests when optional corpora aren't embedded

Since 51c0f4e split the corpora (only vul embedded by default; wuj/drb/grb
behind -tags fullbible), `go test ./...` on the default build was red across six
packages -- every failure was a test assuming an optional corpus is present.

Guard those assertions with a skip keyed on bible.Meta(code), so they run under
-tags fullbible and skip -- not fail -- on the default vul-only build. Mixed
tests are split into subtests so the always-embedded vul assertions and pure
logic (pl->vul fallback, explicit passthrough, bt-rejection, i18n labels) keep
running on both builds. Test-only change; no product code or corpora touched.

- internal/bible: TestVerses, TestLookup, TestCorpusBooks, TestChapters,
  TestGrbNoApparatusMarkers, TestCrossChapterRange* (requireCorpus helper).
- internal/cli, config, render, tui, web: the same pattern for their
  corpus-dependent tests.
- Fixes an index-out-of-range panic in internal/tui's reader tests that was
  aborting the package binary and masking 3 further corpus-absence failures
  (TestReaderBookmarkFlow, TestReaderChapterJump, TestReaderRemembersPlace).

Verified: `go test ./...` and `go test -tags fullbible ./...` both green (0 FAIL);
guards active only on the default build (29 skips vs 1 unrelated pre-existing);
gofmt and go vet clean.

1 files changed, 22 insertions, 15 deletions

diff --git a/internal/bible/ref_test.go b/internal/bible/ref_test.go
index 9473123..0c81a40 100644
--- a/internal/bible/ref_test.go
+++ b/internal/bible/ref_test.go
@@ -14,22 +14,29 @@ func TestSplitRef(t *testing.T) {
 }
 
 func TestLookup(t *testing.T) {
-	vs, missing := Lookup("wuj", "John 20:1,11-18")
-	if len(missing) != 0 {
-		t.Fatalf("missing = %v", missing)
-	}
-	if len(vs) == 0 || vs[0].Verse != 1 {
-		t.Fatalf("first verse = %+v", vs)
-	}
-	last := vs[len(vs)-1]
-	if last.Verse != 18 {
-		t.Errorf("last verse = %d want 18", last.Verse)
-	}
-	// Deuterocanon now present in vul + drb (Clementine Vulgate / Douay-Rheims).
+	t.Run("wuj", func(t *testing.T) {
+		requireCorpus(t, "wuj")
+		vs, missing := Lookup("wuj", "John 20:1,11-18")
+		if len(missing) != 0 {
+			t.Fatalf("missing = %v", missing)
+		}
+		if len(vs) == 0 || vs[0].Verse != 1 {
+			t.Fatalf("first verse = %+v", vs)
+		}
+		last := vs[len(vs)-1]
+		if last.Verse != 18 {
+			t.Errorf("last verse = %d want 18", last.Verse)
+		}
+	})
+	// Deuterocanon in the always-embedded Clementine Vulgate.
 	if vs, m := Lookup("vul", "Wisdom 3:1"); len(m) != 0 || len(vs) == 0 {
 		t.Errorf("vul Wisdom 3:1: missing=%v verses=%d (deuterocanon should resolve)", m, len(vs))
 	}
-	if vs, m := Lookup("drb", "Judith 13:22"); len(m) != 0 || len(vs) == 0 {
-		t.Errorf("drb Judith 13:22: missing=%v verses=%d (deuterocanon should resolve)", m, len(vs))
-	}
+	// Deuterocanon in Douay-Rheims (optional corpus).
+	t.Run("drb", func(t *testing.T) {
+		requireCorpus(t, "drb")
+		if vs, m := Lookup("drb", "Judith 13:22"); len(m) != 0 || len(vs) == 0 {
+			t.Errorf("drb Judith 13:22: missing=%v verses=%d (deuterocanon should resolve)", m, len(vs))
+		}
+	})
 }