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/book_chapter_doyle.toml

@@ -0,0 +1,17 @@
+# Source: CMOS official citation guide (chicagomanualofstyle.org), 18th ed.
+# Chapter in an edited book. CMOS 18 drops the chapter page range from the
+# bibliography entry (kept in notes only).
+source = "CMOS official citation guide (chicagomanualofstyle.org/tools_citationguide/citation-guide-1.html)"
+type = "chapter"
+tags = ["chapter", "edited-volume"]
+canary = true
+messy_input = "kathleen doyle, 'the queen mary psalter,' in The Book by Design: The Remarkable Story of the World's Greatest Invention, P. J. M. Marks and Stephen Parkin eds., Chicago: U of Chicago Press, 2023, pp. 114-120."
+expected_bibliography = "Doyle, Kathleen. \"The Queen Mary Psalter.\" In *The Book by Design: The Remarkable Story of the World's Greatest Invention*, edited by P. J. M. Marks and Stephen Parkin. University of Chicago Press, 2023."
+
+[canonical]
+author = "Doyle, Kathleen"
+chapter_title = "The Queen Mary Psalter"
+book_title = "The Book by Design: The Remarkable Story of the World's Greatest Invention"
+editors = "edited by P. J. M. Marks and Stephen Parkin"
+publisher = "University of Chicago Press"
+year = 2023