fix(plex): plain text decodes only well-formed character references

html.unescape also decodes the legacy forms without a semicolon, so prose like
"AT&notice" came out as "AT¬ice". The show and collection sync paths are
now tested too.

backend/tests/test_plex_plaintext.py

@@ -8,6 +8,7 @@ summary path and the HU overlay store through it, and migration 0101 cleaned the
 import pytest
 from alembic import command
 from alembic.config import Config
+from sqlalchemy import select
 from sqlalchemy.orm import Session
 
 from app.db import engine
@@ -15,7 +16,8 @@ from app.models import PlexCollection, PlexItem, PlexLibrary, PlexShow
 from app.plex.detail import rich_detail
 from app.plex.overlay import sync_overlay
 from app.plex.plaintext import plain_text
-from app.plex.sync import _apply_item
+from app.plex import sync
+from app.plex.sync import _apply_item, _upsert_collection
 
 HU_SUMMARY = "<p>A műsorban minden p&aacute;rosnak stoppal kell eljutnia.</p>"
 
@@ -29,6 +31,9 @@ HU_SUMMARY = "<p>A műsorban minden p&aacute;rosnak stoppal kell eljutnia.</p>"
         ("<b>Bold</b> &amp; <i>more</i>", "Bold & more"),
         # Prose that only looks like markup stays as written.
         ("a < b and 1 <3 you", "a < b and 1 <3 you"),
+        # Only a reference with its semicolon is one: an ampersand in prose stays as written.
+        ("AT&notice, R&copy and H&M", "AT&notice, R&copy and H&M"),
+        ("&#233;t&#xE9; &copy;", "été ©"),
         ("Plain summary.", "Plain summary."),
         ("  padded  ", "padded"),
         ("<p></p>", None),
@@ -46,6 +51,32 @@ def test_the_item_sync_stores_a_summary_as_plain_text():
     assert row.summary == "A műsorban minden párosnak stoppal kell eljutnia."
 
 
+def test_the_show_sync_stores_a_summary_as_plain_text(db, monkeypatch):
+    lib = PlexLibrary(plex_key="2", title="Shows", kind="show", enabled=True)
+    db.add(lib)
+    db.commit()
+    meta = {"ratingKey": "s1", "title": "Show", "summary": HU_SUMMARY}
+
+    def listing(_plex, _key, typ, progress=None):
+        if progress is not None:
+            progress["complete"] = True
+        return [meta] if typ == sync._TYPE_SHOW else []
+
+    monkeypatch.setattr(sync, "_paginate", listing)
+    sync._sync_shows(db, object(), lib, {"shows": 0, "seasons": 0, "episodes": 0})
+    db.commit()
+    show = db.execute(select(PlexShow).where(PlexShow.rating_key == "s1")).scalar_one()
+    assert show.summary == "A műsorban minden párosnak stoppal kell eljutnia."
+
+
+def test_a_collection_stores_its_summary_as_plain_text(db):
+    lib = PlexLibrary(plex_key="1", title="Movies", kind="movie", enabled=True)
+    db.add(lib)
+    db.flush()
+    col = _upsert_collection(db, None, "c1", lib.id, {"title": "C", "summary": "<p>A &amp; B</p>"})
+    assert col.summary == "A & B"
+
+
 def test_a_fetched_tagline_is_plain_text():
     assert rich_detail({"tagline": "<i>An offer</i> &amp; more"})["tagline"] == "An offer & more"