fix(node): stop a numbered saga all matching its first film

Every "<Saga> Episode <N> - <subtitle>" file in a numbered franchise
resolved to the series' first entry (a real, older film). `sequel_variants`
stripped "Episode <N>" and offered the bare "<Saga>" as a candidate query;
that matches the first film's original_title at ratio 1.0 and beat PASS 1's
correct-but-lower hit. A franchise's bare name is very often a real,
different film.

When a Part/Episode/Chapitre/… keyword carried the index, sequel_variants
no longer emits the bare base — only "<base> <digit>" and "<base> <roman>".
Without a keyword ("<Franchise> 3") the bare base is still offered, so that
fix is untouched. Verified live against TMDB: the franchise's episodes each
resolve to their own entry; the earlier numbered-sequel, two-part-film and
franchise-subtitle regressions all hold.

docs/mediacenter.md §10.3.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_018BMLQjqFGCize2KtNBT79v

1 files changed, 14 insertions, 3 deletions

diff --git a/packages/meshbay-node/tests/test_title_parse.py b/packages/meshbay-node/tests/test_title_parse.py
index 045635f..56f4e20 100644
--- a/packages/meshbay-node/tests/test_title_parse.py
+++ b/packages/meshbay-node/tests/test_title_parse.py
@@ -80,16 +80,27 @@ def test_sequel_variants_roman_numeral_offers_the_digit_form():
     assert "Old Frontier 3" in v
 
 
-def test_sequel_variants_strips_a_part_keyword_wrapper():
+def test_sequel_variants_rewrites_a_part_keyword_index_but_keeps_the_name():
+    # §10.1/V14: with a "Part"/"Episode"/… keyword the bare base is
+    # withheld — "Some Saga" alone collides with a franchise-origin film.
     v = sequel_variants("Some Saga Part 2")
-    assert "Some Saga" in v
     assert "Some Saga II" in v
+    assert "Some Saga 2" in v
+    assert "Some Saga" not in v
 
 
 def test_sequel_variants_reads_a_spelled_out_index():
     v = sequel_variants("Story Chapter Three")
-    assert "Story" in v
     assert "Story 3" in v and "Story III" in v
+    assert "Story" not in v  # keyword present -> no bare base
+
+
+def test_sequel_variants_star_wars_shape_does_not_offer_the_bare_franchise():
+    # Every "<Franchise> Episode <N>" was matching the 1977 original
+    # because the "Franchise" variant hit it at ratio 1.0 (§10.1/V14).
+    v = sequel_variants("Star Wars Episode III")
+    assert "Star Wars" not in v
+    assert "Star Wars 3" in v
 
 
 def test_sequel_variants_ignores_a_trailing_word_that_is_not_an_index():