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/video_cowan_ted.toml

@@ -0,0 +1,18 @@
+# Source: CMOS official citation guide (chicagomanualofstyle.org), 18th ed.
+# Video (TED Talk). Video title in quotes (not italics since it's a talk, not
+# a standalone work). Venue, date, format, duration, URL.
+source = "CMOS official citation guide (chicagomanualofstyle.org/tools_citationguide/citation-guide-1.html)"
+type = "video"
+tags = ["video", "ted"]
+canary = true
+messy_input = "Vaitea Cowan. How Green Hydrogen Could End the Fossil Fuel Era. TED Talk. Vancouver BC. April 2022. 9 minutes 15 seconds. https://www.ted.com/talks/vaitea_cowan_how_green_hydrogen_could_end_the_fossil_fuel_era"
+expected_bibliography = "Cowan, Vaitea. \"How Green Hydrogen Could End the Fossil Fuel Era.\" TED Talk, Vancouver, BC, April 2022. Video, 9 min., 15 sec. https://www.ted.com/talks/vaitea_cowan_how_green_hydrogen_could_end_the_fossil_fuel_era."
+
+[canonical]
+author = "Cowan, Vaitea"
+title = "How Green Hydrogen Could End the Fossil Fuel Era"
+venue = "TED Talk, Vancouver, BC"
+date = "April 2022"
+format = "Video"
+duration = "9 min., 15 sec."
+url = "https://www.ted.com/talks/vaitea_cowan_how_green_hydrogen_could_end_the_fossil_fuel_era"