Expand exemplar corpus to 14 across 8 CMOS 18 source types

Add 11 new exemplars pulled verbatim from the CMOS official quick guide
(chicagomanualofstyle.org/tools_citationguide/citation-guide-1.html):

- book_two_authors_binder: Binder & Kidder (two-author book)
- book_chapter_doyle: Doyle in Marks & Parkin (chapter in edited volume,
  no page range per CMOS 18)
- book_translated_liu: Liu Xinwu, trans. Tiang (translated book, non-
  Western name not comma-inverted)
- book_edition_borel: Borel, 2nd ed. via EBSCOhost (edition + database)
- book_ebook_roy: Roy, Kindle format
- journal_many_authors_snyder: 7 authors in PLOS ONE, exercises the
  CMOS 18 "first 3 + et al." threshold and article-ID page format
- magazine_mead: New Yorker (tests leading-"The" drop)
- newspaper_blum: NYT with URL (tests abbreviation expansion)
- social_media_cmos_facebook: Facebook post with case preservation
- podcast_ober: Pushkin podcast with season/episode/duration
- video_cowan_ted: TED Talk with venue and duration

Every exemplar is marked canary=true — we want byte-exact regression
detection on all of them. Source citations and CMOS rule justifications
are in the TOML doc comments.

All 14 canonical outputs lint clean under LINTER_VERSION v0.2.0. The
harness will score them in the following commit.

exemplars/podcast_ober.toml

@@ -0,0 +1,20 @@
+# Source: CMOS official citation guide (chicagomanualofstyle.org), 18th ed.
+# Podcast episode. Podcast series title is italicized like a book; episode
+# title is in quotes. Duration appears after the format label.
+source = "CMOS official citation guide (chicagomanualofstyle.org/tools_citationguide/citation-guide-1.html)"
+type = "podcast"
+tags = ["podcast", "audio"]
+canary = true
+messy_input = "Lauren Ober (host). The Loudest Girl in the World (podcast). S1E2 - 'Goodbye, Routine; Hello, Meltdown!' Pushkin Industries. Released Sept 13 2022. 41:37. https://www.pushkin.fm/podcasts/loudest-girl-in-the-world"
+expected_bibliography = "Ober, Lauren, host. *The Loudest Girl in the World*. Season 1, episode 2, \"Goodbye, Routine; Hello, Meltdown!\" Pushkin Industries, September 13, 2022. Podcast, 41 min., 37 sec. https://www.pushkin.fm/podcasts/loudest-girl-in-the-world."
+
+[canonical]
+host = "Ober, Lauren, host"
+podcast = "The Loudest Girl in the World"
+season_episode = "Season 1, episode 2"
+episode_title = "Goodbye, Routine; Hello, Meltdown!"
+publisher = "Pushkin Industries"
+date = "September 13, 2022"
+format = "Podcast"
+duration = "41 min., 37 sec."
+url = "https://www.pushkin.fm/podcasts/loudest-girl-in-the-world"