docs(milestone): complete v0.4-operator-tier — v0.1.9 tagged, milestone release, merged to main

v0.4 (Operator Tier — Cohort Dashboard + Auth + Postgres) milestone complete.

Phases:
  ✓ P0  pre-execution (planning)        → v0.1.6
  ✓ P1  operator foundation (Postgres+auth+VC migration) → v0.1.7
  ✓ P2  cohort dashboard + aggregation   → v0.1.8
  ✓ P3  final review + ship              → v0.1.9 (= v0.4 milestone release)

Requirements covered (8/8):
  REQ-MT-01 (Postgres store), REQ-MT-02 (aggregation pipeline),
  REQ-AUTH-01 (operator auth), REQ-DASH-01 (cohort dashboard),
  REQ-NFR-AUTH-01 (auth NFRs), REQ-NFR-MT-01 (Postgres-in-LXC),
  REQ-NFR-DASH-01 (k-anonymity ≥10), REQ-NFR-DASH-02 (freshness ≤24h)

Grill MUSTs honored (6/6): G-008, G-011, G-027, G-031, G-038, G-041

Tests: 317 pytest pass, 36 skip (Postgres-requiring), 0 fail; 17/17 vitest pass
Review: APPROVE_WITH_NOTES (6/6 personas, 0 P0, 8 P1+ carry-forward)
Audit: HEALTHY (reconstruction PASS, 8/8 REQ, 6/6 grill)

---ci---
project: praxis
phase: 3
milestone: v0.4
status: complete
phase_role: final
milestone_complete: true
milestone_merged_to_main: true
tag: v0.1.9
requirements:
  covered: [REQ-MT-01, REQ-MT-02, REQ-AUTH-01, REQ-DASH-01, REQ-NFR-AUTH-01, REQ-NFR-MT-01, REQ-NFR-DASH-01, REQ-NFR-DASH-02]
  partial: []
---/ci---

scripts/proxmox/lxc-clone.sh

@@ -40,7 +40,10 @@ upid=$(pve_curl POST "$create_path" \
     "hostname=${hostname}" \
     "storage=${storage}" \
     "rootfs=${storage}:16" \
-    "memory=${PROXMOX_MEMORY_MB:-4096}" \
+    # v0.4: 6144MB default (was 4096 in v0.2). Postgres ~400MB + praxis
+    # ~500MB + Docker daemon ~200MB + build headroom ~1GB + margin
+    # (REQ-NFR-MT-01). Override with PROXMOX_MEMORY_MB if needed.
+    "memory=${PROXMOX_MEMORY_MB:-6144}" \
     "net0=name=eth0,bridge=vmbr0,ip=dhcp" \
     "arch=amd64" \
     "features=nesting=1")