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, 42 insertions, 6 deletions

diff --git a/internal/tui/reader_test.go b/internal/tui/reader_test.go
index 9d324ba..7bce759 100644
--- a/internal/tui/reader_test.go
+++ b/internal/tui/reader_test.go
@@ -30,6 +30,18 @@ func key(m ReaderModel, k tea.KeyMsg) ReaderModel {
 	return nm.(ReaderModel)
 }
 
+// requireCorpus skips the test when corpus `code` is not embedded in this
+// build. The optional corpora (wuj, drb, grb) compile in only with
+// `-tags fullbible` (or when dropped into the user corpora dir); mirrors the
+// helper in internal/bible so these tests run under fullbible and skip -- not
+// fail -- on the default vul-only build.
+func requireCorpus(t *testing.T, code string) {
+	t.Helper()
+	if _, ok := bible.Meta(code); !ok {
+		t.Skipf("corpus %q not embedded; build with -tags fullbible", code)
+	}
+}
+
 func runes(s string) tea.KeyMsg { return tea.KeyMsg{Type: tea.KeyRunes, Runes: []rune(s)} }
 
 func win(m ReaderModel, w, h int) ReaderModel {
@@ -55,6 +67,8 @@ func TestReaderFilterAndOpen(t *testing.T) {
 	nm, _ := m.Update(tea.WindowSizeMsg{Width: 80, Height: 24})
 	m = nm.(ReaderModel)
 	m = key(m, runes("jn"))
+	// Fuzzy filtering and entering read mode come from the book table and the
+	// model's state machine -- independent of any corpus being embedded.
 	if len(m.matches) == 0 || m.books[m.matches[0]].Canonical != "John" {
 		t.Fatalf("filter 'jn' top = %v", m.books[m.matches[m.pickSel]])
 	}
@@ -62,15 +76,25 @@ func TestReaderFilterAndOpen(t *testing.T) {
 	if m.mode != modeRead {
 		t.Fatalf("did not enter read mode")
 	}
-	if m.books[m.bookIdx].Canonical != "John" || len(m.verses) == 0 {
-		t.Errorf("opened book=%q verses=%d", m.books[m.bookIdx].Canonical, len(m.verses))
-	}
-	if !strings.Contains(m.View(), "1") { // chapter 1 header
-		t.Errorf("read view missing chapter:\n%s", m.View())
-	}
+	// The reader's first version is wuj (see enReader): its verses and chapter
+	// header need the optional wuj corpus embedded.
+	t.Run("wuj verses", func(t *testing.T) {
+		requireCorpus(t, "wuj")
+		if m.books[m.bookIdx].Canonical != "John" || len(m.verses) == 0 {
+			t.Errorf("opened book=%q verses=%d", m.books[m.bookIdx].Canonical, len(m.verses))
+		}
+		if !strings.Contains(m.View(), "1") { // chapter 1 header
+			t.Errorf("read view missing chapter:\n%s", m.View())
+		}
+	})
 }
 
 func TestReaderChapterAndVersion(t *testing.T) {
+	// Whole-test guard: the reader's first version is wuj (see enReader), so the
+	// very first read-mode step below indexes m.chapters[m.chapPos] -- which
+	// panics on an empty chapter list when wuj is not embedded. The chapter
+	// stepping and version cycling that follow are all a wuj reading session.
+	requireCorpus(t, "wuj")
 	m := enReader(t)
 	nm, _ := m.Update(tea.WindowSizeMsg{Width: 80, Height: 24})
 	m = nm.(ReaderModel)
@@ -107,6 +131,10 @@ func TestReaderFuzzyScore(t *testing.T) {
 }
 
 func TestReaderBookmarkFlow(t *testing.T) {
+	// The whole flow reads and bookmarks verses of John from wuj (the reader's
+	// first version); "m" only opens the verse picker when len(verses)>0, so
+	// the optional wuj corpus must be embedded.
+	requireCorpus(t, "wuj")
 	m := enReader(t)
 	m = win(m, 80, 24)
 	m = key(m, runes("jn"))
@@ -166,6 +194,10 @@ func TestReaderBookmarkFlow(t *testing.T) {
 }
 
 func TestReaderChapterJump(t *testing.T) {
+	// Reads John from wuj (the reader's first version); "c" only opens the
+	// chapter-jump prompt when the book has >1 chapter loaded, so the optional
+	// wuj corpus must be embedded.
+	requireCorpus(t, "wuj")
 	m := enReader(t)
 	m = win(m, 80, 24)
 	m = key(m, runes("jn"))
@@ -224,6 +256,10 @@ func TestReaderChapterJump(t *testing.T) {
 }
 
 func TestReaderRemembersPlace(t *testing.T) {
+	// Persisting/restoring a reading position needs real verses (savePlace
+	// no-ops when len(verses)==0); the reader's first version is wuj, so the
+	// optional wuj corpus must be embedded.
+	requireCorpus(t, "wuj")
 	dir := t.TempDir()
 	t.Setenv("XDG_DATA_HOME", dir)
 	tbl, _ := bible.LoadBookTable(nil)