docs(req-073): Approved → Implemented (BAT-037 / CHG-20260612-IMPL)

available_slots capacity hint — AC-3 반전·AC-6 신규, 16 tests passed.

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

docs/srs/Interface/req-073_slots-req-rpc-contract.md

@@ -1,6 +1,6 @@
 # req-073: 전략 read 표면 — `trex.slots.req` RPC 계약 (filter/spy, snapshot.req 즉시 교체)
 
-- Status: Approved
+- Status: Implemented
 - Type: Interface
 - Priority: High
 - Owner: project maintainers
@@ -37,6 +37,12 @@
 
 ## Change Log
 
+### CHG-20260612-IMPL
+- Date: 2026-06-12
+- Author: Justin Ko
+- Type: status
+- Summary: Approved → Implemented (confirm-req-implemented). 근거: BAT-037 (release-candidate) — AC-3 반전(available_slots 포함)·AC-6 신규(null/잔여/0 클램프) 16 tests passed, 423 전체 회귀 없음. Blocking Issues 없음.
+
 ### CHG-20260612-01
 - Date: 2026-06-12
 - Author: Justin Ko