feat: scrape tournament meta from Wikipedia, drop world_cup.csv

Add worldcup.meta.json per year with host, teams_count, winner, runner_up,
third_place, fourth_place — derived from match results (Final/Third-place
match) with infobox as fallback for edge cases like 1950's round-robin final.

Fix infobox host extraction to handle <br>-separated multi-host entries
(2002: Japan / South Korea). Fix squad scraper to filter out zero-player
phantom sections that Wikipedia appends (References, Captains, etc.).

Drop app/data/world_cup.csv and the PLACEMENTS/parseCsv code in seed.ts —
all tournament metadata now comes from the scraped JSON files.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

app/data/wikipedia/1994/worldcup.squads.json

@@ -3286,13 +3286,5 @@
         "date_of_birth": "1972-08-18"
       }
     ]
-  },
-  {
-    "name": "Captains",
-    "players": []
-  },
-  {
-    "name": "Goalkeepers",
-    "players": []
   }
 ]