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/magazine_mead.toml

@@ -0,0 +1,14 @@
+# Source: CMOS official citation guide (chicagomanualofstyle.org), 18th ed.
+# Magazine article. No volume/issue required; full date instead.
+source = "CMOS official citation guide (chicagomanualofstyle.org/tools_citationguide/citation-guide-1.html)"
+type = "magazine"
+tags = ["magazine"]
+canary = true
+messy_input = "Rebecca Mead, 'Terms of Aggrievement', The New Yorker, Dec. 18, 2023."
+expected_bibliography = "Mead, Rebecca. \"Terms of Aggrievement.\" *New Yorker*, December 18, 2023."
+
+[canonical]
+author = "Mead, Rebecca"
+article_title = "Terms of Aggrievement"
+magazine = "New Yorker"
+date = "December 18, 2023"