docs(audit): fix PROJECT.md v0.5 status drift (in progress → complete)

Audit (ci-audit workflow) found PROJECT.md line 64 said 'v0.5 — Bearers
Runtime (in progress...)' but the milestone is COMPLETE (ROADMAP.md
COMPLETE, checkpoint milestone_complete=true, release v0.4.8 shipped).
Fixed to 'complete' to match reconstruction state.

---ci---
project: oy
phase: 8
milestone: v0.5
status: audit
requirements:
  covered: []
  partial: []
---/ci---

.ciagent/oy/PROJECT.md

@@ -61,7 +61,7 @@ OpenYield (OY) is a durable, anti-greed, jurisdiction-light financial layer —
 - D-009: Rebased history to fix v1.0 → v0.1 in ---ci--- blocks
 
 ## Milestone
-v0.5 — Bearers Runtime (in progress; feature type; tags run on the v0.4.x patch line)
+v0.5 — Bearers Runtime (complete; feature type; tags ran on the v0.4.x patch line)
 
 ### v0.5 Scope (Live-runtime promotions of the v0.3 Bearers skeletons)