docs: B-0 — deploy the BFF and read what autoconfiguration actually chose

The authorized client repository is AuthenticatedPrincipalOAuth2AuthorizedClientRepository, keyed by principal with no session id in it, which is the mechanism behind the sharing problem Q1 and Q3 describe. Sharing a store does not fix a lookup key.

Five problems on the way in: only build output was committed under bff/, a duplicate YAML key broke the image build and was invisible until the full log was captured, env placeholders without defaults broke the tests, actuator was behind the login redirect so a 200 was the login page, and the 117KB beans response failed through the proxy.

Deploying two replicas made the login itself fail before any experiment started, because the authorization request lives in per-instance memory and the callback lands elsewhere.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>

docs/evidence/b0-bff-redis-deploy/02-autoconfiguration.txt

@@ -0,0 +1,13 @@
+=== B-0: 자동구성이 실제로 고른 구현체 ===
+  Q1 확인한 사실: "코드에 저장소를 직접 생성하는 Bean 이 없기 때문에,
+   어떤 구현체가 실제로 사용되는지는 자동구성 결과까지 확인해야 정확하게 알 수 있다"
+
+  File "<stdin>", line 9
+    print(f"    {name:46} {t.rsplit(\".\",1)[-1]}")
+                                     ^
+SyntaxError: unexpected character after line continuation character
+
+=== HttpSession 은 어디에 있는가 (서블릿 컨테이너 기본) ===
+
+=== 외부 진입점 ===
+  https://app1.hyeonworks.com/  HTTP 200