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_two_authors_binder.toml

@@ -0,0 +1,14 @@
+# Source: CMOS official citation guide (chicagomanualofstyle.org), 18th ed.
+# Two-author book. Both names listed; second author NOT inverted.
+source = "CMOS official citation guide (chicagomanualofstyle.org/tools_citationguide/citation-guide-1.html)"
+type = "book"
+tags = ["book", "two-authors"]
+canary = true
+messy_input = "binder amy j and jeffrey l kidder, the channels of student activism: how the left and right are winning (and losing) in campus politics today. chicago: University of Chicago Press, 2022."
+expected_bibliography = "Binder, Amy J., and Jeffrey L. Kidder. *The Channels of Student Activism: How the Left and Right Are Winning (and Losing) in Campus Politics Today*. University of Chicago Press, 2022."
+
+[canonical]
+authors = "Binder, Amy J., and Jeffrey L. Kidder"
+title = "The Channels of Student Activism: How the Left and Right Are Winning (and Losing) in Campus Politics Today"
+publisher = "University of Chicago Press"
+year = 2022