tui(reader): filter bookmarks by tag, and show tags in the list

Bookmarks stored tags but the list neither showed them nor let you use them.
Now each row shows "Ref — note  #tag1 #tag2", and `/` opens a live tag filter
(case-insensitive substring over a bookmark's tags): type to narrow, Enter keeps
the filter while j/k navigate the filtered list, Esc clears it. Navigation,
open and delete all act on the visible (filtered) list. Reuses the store's
existing tag data; help keybar (en/pl) updated; test covers filter/keys.

1 files changed, 49 insertions, 0 deletions

diff --git a/internal/tui/reader_test.go b/internal/tui/reader_test.go
index 7bce759..da8d4d4 100644
--- a/internal/tui/reader_test.go
+++ b/internal/tui/reader_test.go
@@ -49,6 +49,55 @@ func win(m ReaderModel, w, h int) ReaderModel {
 	return nm.(ReaderModel)
 }
 
+func TestReaderBookmarkTagFilter(t *testing.T) {
+	m := enReader(t)
+	m.marks = []bookmarks.Bookmark{
+		{ID: "1", Book: "John", Chapter: 3, Verse: 16, Tags: []string{"faith"}},
+		{ID: "2", Book: "Psalms", Chapter: 23, Verse: 1, Tags: []string{"work", "prayer"}},
+		{ID: "3", Book: "Matthew", Chapter: 5, Verse: 3, Tags: []string{"prayer"}},
+	}
+	m.mode = modeBookmarks
+
+	if got := len(m.visMarks()); got != 3 {
+		t.Fatalf("unfiltered visible = %d, want 3", got)
+	}
+
+	// "/" enters filter input; typing narrows to the two 'prayer' bookmarks.
+	m = key(m, runes("/"))
+	if !m.markFiltering {
+		t.Fatal(`"/" did not enter filter input`)
+	}
+	for _, c := range []string{"p", "r", "a", "y"} {
+		m = key(m, runes(c))
+	}
+	if got := len(m.visMarks()); got != 2 {
+		t.Fatalf(`filter "pray" visible = %d, want 2 (Psalms, Matthew)`, got)
+	}
+
+	// Enter keeps the filter and leaves input mode.
+	m = key(m, tea.KeyMsg{Type: tea.KeyEnter})
+	if m.markFiltering || m.markFilter != "pray" {
+		t.Fatalf("after enter: filtering=%v filter=%q", m.markFiltering, m.markFilter)
+	}
+
+	// Case-insensitive substring: "WORK" matches the 'work' tag (1 bookmark).
+	m.markFilter = "WORK"
+	if got := len(m.visMarks()); got != 1 {
+		t.Fatalf(`filter "WORK" visible = %d, want 1`, got)
+	}
+
+	// Esc clears an active filter, back to all.
+	m.markFilter = "work"
+	m.markFiltering = false
+	m = key(m, tea.KeyMsg{Type: tea.KeyEsc})
+	if m.markFilter != "" {
+		t.Fatalf("esc did not clear filter, got %q", m.markFilter)
+	}
+	if got := len(m.visMarks()); got != 3 {
+		t.Fatalf("after clearing filter, visible = %d, want 3", got)
+	}
+}
+
 func TestReaderInit(t *testing.T) {
 	m := enReader(t)
 	if m.mode != modePick {