docs: batch 상태 released 동기화(REL-001/002) + README 현행화(거래내역/실현PnL API)

batch drift 정합 — REL-001(BAT-001~016)·REL-002(BAT-017) released에 맞춰
batches/index 및 개별 index 상태를 release-candidate→released 동기화(17건).
README: bootstrap 문구 제거, dcy-007 엔드포인트(GET /trades·/pnl/realized) 추가,
planned-next 현행화. 코드 무변경.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01VHtM5Ws1HKCKQ4JGi6GRb5

docs/batches/bat-008_20260521_token-surface-docs/index.md

@@ -1,6 +1,6 @@
 # BAT-008: dcy-004 토큰 surface baseline 문서화
 
-- Status: release-candidate
+- Status: released
 - Profile: standard
 - Source Discovery: dcy-004
 - Included REQ: REQ-019, REQ-020, REQ-021, REQ-024