docs(milestone): complete v0.16 release binary asset fix

All 2 requirements (REQ-183,184) complete. Release pipeline now
builds and uploads binary assets to Gitea releases.

v0.15.1 release confirmed with 2 binary assets:
  - orca-v0.15.1-linux-amd64.tar.gz (7.6MB)
  - SHA256SUMS (98 bytes)

---ci---
project: orca
phase: 2
milestone: v0.16
status: complete
requirements:
  covered: [183, 184]
  partial: []
---/ci---

.ciagent/ROADMAP.md

@@ -746,7 +746,7 @@ line: `v0.14.0` (P0) ... `v0.14.2` (P2 final = v0.15 milestone release).
 - [x] Phase 1: Gitea Actions workflow + .coreci.yml kaniko rewrite (REQ-180,181) — tag `v0.14.1`
 - [x] Phase 2: Final review + ship + audit (milestone release) — tag `v0.14.2` = **v0.15 milestone release**
 
-## Milestone v0.16: Release Binary Asset Fix — **IN PROGRESS**
+## Milestone v0.16: Release Binary Asset Fix — **COMPLETE**
 
 **Scope**: fix the root cause of releases shipping with zero binary
 assets. v0.15 added a Gitea Actions workflow but it never executed
@@ -765,5 +765,5 @@ pipeline to actually build and upload binaries.
 line: `v0.15.0` (P0) ... `v0.15.2` (P2 final = v0.16 milestone release).
 
 - [x] Phase 0: Pre-execution (SPECIFY→CLARIFY→RESEARCH→PLAN→GRILL) — tag `v0.15.0`
-- [ ] Phase 1: Fix Gitea Actions clone auth + rewrite .coreci.yml to CoreCI native format (REQ-183,184) — tag `v0.15.1`
-- [ ] Phase 2: Final review + ship + audit (milestone release) — tag `v0.15.2` = **v0.16 milestone release**
+- [x] Phase 1: Fix Gitea Actions clone auth + rewrite .coreci.yml to CoreCI native format (REQ-183,184) — tag `v0.15.1`
+- [x] Phase 2: Final review + ship + audit (milestone release) — tag `v0.15.2` = **v0.16 milestone release**