fix(podcasts): library switcher leaked literal "continue" and the podcasts option

The D13 podcast exclusion (9a148c23) was written as a templ
`if !IsBookLibrary(...) { continue }` — but templ markup control flow
has NO continue STATEMENT: codegen emitted the word as a TEXT node
(visible junk between options on every page's library subbar) and
rendered the podcasts option anyway, defeating the exclusion. The real
browser sweep caught what every Go/API test structurally cannot:
generated markup that renders wrong yet compiles clean.

Rewritten as an inverted guard (the idiomatic templ skip). New render
pin TestLibrarySwitcherExcludesPodcasts fails on both halves of the
original leak — the literal text AND the presence of the podcasts
option — so this codegen gotcha class stays tripped-wired.

templates/partials_render_test.go

@@ -106,3 +106,27 @@ func TestUnlinkedBooksPageRender(t *testing.T) {
 		}
 	}
 }
+
+// The library switcher's D13 podcast exclusion must hold at the
+// presentation layer — and the templ `continue` statement leak (codegen
+// emits it as literal TEXT, browser sweep 2026-10-30) must never return.
+func TestLibrarySwitcherExcludesPodcasts(t *testing.T) {
+	var b strings.Builder
+	libs := []LibraryData{
+		{ID: "l1", Name: "Ebooks", TypeName: "books", MediaCount: 5},
+		{ID: "l2", Name: "Podcasts", TypeName: "podcasts", MediaCount: 235},
+	}
+	if err := LibrarySwitcher(libs, "l1", "", nil).Render(context.Background(), &b); err != nil {
+		t.Fatalf("LibrarySwitcher: %v", err)
+	}
+	out := b.String()
+	if strings.Contains(out, "Podcasts (235)") {
+		t.Error("switcher leaked the podcasts library into the book switcher")
+	}
+	if strings.Contains(out, "continue") {
+		t.Error("switcher rendered the literal text `continue` (templ has no continue statement)")
+	}
+	if !strings.Contains(out, "Ebooks (5)") {
+		t.Error("switcher missing the books library")
+	}
+}