First real upload lands: three browser-flow bugs, found by doing it

A Gentle Rain is on BGG (collid 148198034, version 701315 — the
English Bloom edition matched from a shelf photo), verified by
re-fetching the collection. The failures on the way, all in the
login gate the docs called "verified" and none in the version-picker
code they called "unverified":

1. BGG's Sign In is an <a class="btn"> with NO href, so it has no
   implicit link role: get_by_role("link", name="Sign In") matched
   zero elements in EVERY state, and "no Sign In link" was read as
   "already signed in". Every run browsed anonymously.
2. The header hydrates after domcontentloaded, so for a moment
   neither control exists — a check resting on one absence guesses.
   _signed_out() now polls until the page proves one state or the
   other (Sign In vs Sign Out) and raises after 30s rather than
   assume; login is verified by the transition, and the session file
   saves only after that proof.
3. get_by_label("Own") also matched "Prev. Owned" — strict-mode
   violation; the Own checkbox is now matched exactly.

Also: Playwright's multi-line call logs no longer break upload_log.csv
into ragged rows (errors flatten to one line). Three unit tests cover
the hydration window, positive detection, and the undeterminable case.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_016jXZFSTZQKzAC8fqpWSz9g

data/to_update.csv

@@ -1 +1,35 @@
 collid,bgg_id,bgg_name,version_id,version_name
+53429559,240,Britannia,24621,Avalon Hill second edition
+53429530,71,Civilization,24006,Avalon Hill first edition 1981
+53429542,177,Advanced Civilization,24972,English edition
+53429504,3090,Doctor Who: The Game of Time & Space,25782,English edition
+53429482,3585,Sorcerer: The Game of Magical Conflict,211154,SPI Designer's Edition
+53429367,2524,StarForce 'Alpha Centauri': Interstellar Conflict in the 25th Century,219137,SPI boxed designer's edition
+53429816,224,History of the World,20727,Avalon Hill/Hasbro edition
+53429636,9209,Ticket to Ride,294188,English edition 2012 with Spiel des Jahres logo
+53430595,13,Catan,347121,English edition 2016
+53430485,1219,Labyrinth,488621,English edition 2017
+53429649,137909,Bugs in the Kitchen,216474,English first edition
+53430142,27710,Catan Dice Game,606657,English edition 2018
+53429953,169784,Castle Panic: The Dark Titan,260454,English first edition
+53429666,147370,Robot Turtles,231664,English second edition
+53430559,43443,Castle Panic,103068,"English edition, fourth printing"
+53429632,24310,The Red Dragon Inn,374258,English fifth edition
+53429748,39856,Dixit,296529,Asmodee/Libellud English edition 2015
+53430257,35505,Walk the Plank!,781669,English MDG-4311 edition
+53430020,164,"Before I Kill You, Mister Bond",28465,"Cheapass black and white ""Better Edition"" edition"
+53429887,65244,Forbidden Island,31208,English edition 051210
+53429908,95386,Tempurra,290572,English edition
+53430200,258,Fluxx,20840,Looney Labs Version v2.1
+53430332,188614,Simon's Cat Card Game,779792,"English edition, second printing"
+53429850,4324,Risk: The Lord of the Rings,26859,English edition 2002
+53429933,1927,Munchkin,28144,"English edition 2009, 15th printing"
+53430007,1784,Dark Cults,110926,First edition
+53429986,176,Give Me the Brain!,27673,Czech edition
+53430040,257,Kill Doctor Lucky,520364,"Cheapass envelope edition, second printing"
+53612880,153999,"...and then, we held hands.",280845,English edition
+53612866,166976,Consentacle,410382,English Kickstarter edition
+53430652,231302,The Cat Game,361880,English/French edition
+53430517,40692,Small World,294178,English third edition
+53429718,172503,Mage Wars Academy,265107,English edition
+53429642,104710,Wiz-War (Eighth Edition),117685,English first edition