Story 5.3 — Implement infrastructure-versions.yaml placement via atomic write before infra upgrade

**Epic:** #502 — Network Upgrade Workflow (Execute Phase)

Place InfraConfig files from the upgrade directory to their canonical host filesystem locations via
atomic write, before any infra upgrade step executes.

**Acceptance criteria:**
- Generalize to a hardcoded filename→destination mapping. `infrastructure-versions.yaml` → `paths.InfraVersionsPath` (`/opt/solo/weaver/config/infrastructure-versions.yaml`) is the first entry; design for additional InfraConfig files.
- For files with a known parser (e.g. infrastructure-versions.yaml → `ParseInfrastructureVersions`), **parse + validate before placing**; a malformed manifest halts the workflow before any file is written.
- Atomic write (`.tmp` on the destination filesystem, then rename).
- Placement occurs before any CRI-O, kubelet, or Helm upgrade step.
- Failure to place halts the execute workflow (via the DaemonResult handshake).