feat(library): add Star-Spangled Banner + Ode to Joy starter content (#744)

Add two more public-domain starter songs alongside Für Elise, wired into
_BUILTIN_STARTER_SOURCES so they seed into DLC_DIR/starter/ on first run:

- The Star-Spangled Banner (lead) — John Stafford Smith; cleaned the "Unknown"
  artist / placeholder album, author "Fee[dB]ack".
- Ode to Joy (lead/rhythm/bass + drums) — Beethoven. Replaces the raw
  "Ode to Joy (VST Cover)_The Adicts.feedpak" that was committed to main but
  never added to the seed list (so it bundled 23 MB of dead weight and never
  appeared). Fixed metadata (artist Beethoven, year 1824, author "Fee[dB]ack"),
  and repointed the stem from the 22 MB editor WAV to the byte-identical-render
  full.ogg (both exactly 85.324 s), shrinking the pack 23.8 MB -> 1.7 MB.

Add guard tests asserting every _BUILTIN_STARTER_SOURCES entry has its file
committed and that a seed run lands them all — this catches exactly the
listed-but-missing (or committed-but-unlisted) mismatch that left Ode to Joy
un-seeded.

Co-authored-by: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

server.py

@@ -5817,6 +5817,14 @@ _BUILTIN_STARTER_SOURCES: list[tuple[str, str]] = [
         "beethoven-fur_elise.feedpak",
         "content/starter/beethoven-fur_elise.feedpak",
     ),
+    (
+        "star_spangled_banner.feedpak",
+        "content/starter/star_spangled_banner.feedpak",
+    ),
+    (
+        "beethoven-ode_to_joy.feedpak",
+        "content/starter/beethoven-ode_to_joy.feedpak",
+    ),
 ]
 _STARTER_SEED_MARKER = ".starter-content-seeded"
 

tests/test_builtin_starter_seed.py

@@ -181,3 +181,54 @@ def test_seed_does_not_mark_when_source_missing(tmp_path, server_mod, monkeypatc
 
     assert not (dlc / server_mod._BUILTIN_STARTER_SUBDIR / "missing.feedpak").exists()
     assert not (server_mod.CONFIG_DIR / server_mod._STARTER_SEED_MARKER).exists()
+
+
+def test_every_starter_source_file_is_present(server_mod):
+    """Every entry in _BUILTIN_STARTER_SOURCES must have its bundled file on
+    disk — otherwise the all-present gate never fires and NOTHING seeds (a
+    listed-but-missing pack silently disables starter seeding entirely). In CI
+    the checkout is clean, so "on disk" == committed."""
+    root = server_mod._feedBack_server_root()
+    missing = [
+        rel for _, rel in server_mod._BUILTIN_STARTER_SOURCES
+        if not (root / rel).is_file()
+    ]
+    assert not missing, f"listed starter sources missing on disk: {missing}"
+
+
+def test_seed_lands_every_listed_starter_pack(tmp_path, server_mod):
+    """A real seed run copies every listed pack into starter/ and marks done."""
+    root = server_mod._feedBack_server_root()
+    for _, rel in server_mod._BUILTIN_STARTER_SOURCES:
+        if not (root / rel).is_file():
+            pytest.skip(f"starter source not present in checkout: {rel}")
+
+    dlc = tmp_path / "dlc"
+    dlc.mkdir()
+    server_mod._seed_builtin_starter_content(dlc)
+
+    for dest_name, _ in server_mod._BUILTIN_STARTER_SOURCES:
+        dest = dlc / server_mod._BUILTIN_STARTER_SUBDIR / dest_name
+        assert dest.is_file(), f"pack not seeded: {dest_name}"
+    assert (server_mod.CONFIG_DIR / server_mod._STARTER_SEED_MARKER).is_file()
+
+
+def test_no_unlisted_starter_pack_on_disk(server_mod):
+    """The inverse guard: every content/starter/*.feedpak on disk must be wired
+    into _BUILTIN_STARTER_SOURCES. An unlisted pack bundles into builds as dead
+    weight and never seeds — exactly how the raw Ode-to-Joy pack slipped onto
+    main before being wired up. In CI the checkout is clean, so this flags any
+    stray/committed pack that isn't listed."""
+    root = server_mod._feedBack_server_root()
+    listed = {rel for _, rel in server_mod._BUILTIN_STARTER_SOURCES}
+    if not listed:
+        pytest.skip("no starter sources declared")
+    content_dir = (root / next(iter(listed))).parent  # all sources share this dir
+    if not content_dir.is_dir():
+        pytest.skip(f"starter content dir absent: {content_dir}")
+    on_disk = {p.relative_to(root).as_posix() for p in content_dir.glob("*.feedpak")}
+    unlisted = on_disk - listed
+    assert not unlisted, (
+        "committed but not in _BUILTIN_STARTER_SOURCES (would bundle as dead "
+        f"weight and never seed): {sorted(unlisted)}"
+    )