chore: commit pending phase-3 work and add TEST_ACCOUNTS.md

Includes planning artifacts (03-CONTEXT, 03-DISCUSSION-LOG, 03-02-SUMMARY),
integration test script, MinIO/auth/docker fixes, and local dev account reference.

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

.planning/STATE.md

@@ -4,13 +4,13 @@ milestone: v1.0
 milestone_name: milestone
 current_phase: 3
 status: executing
-last_updated: "2026-05-23T14:49:20.062Z"
+last_updated: "2026-05-23T23:47:54.258Z"
 progress:
   total_phases: 5
-  completed_phases: 2
+  completed_phases: 3
   total_plans: 15
-  completed_plans: 13
-  percent: 40
+  completed_plans: 15
+  percent: 60
 ---
 
 # Project State