feat(consensus): NetworkGenesis step for fresh install

Create NetworkGenesis CR during fresh consensus node install to bootstrap from genesis.

Parent epic: #408
Depends on: #1044

### Scope
- Create NetworkGenesis CR after ConsensusCapsule is created
- Wait for genesis completion (roster + address book ConfigMaps produced by operator)
- Skip if NetworkGenesis already exists (idempotent)

### Context
Per HIP-1495/1497, a fresh install has no pre-existing state and bootstraps from genesis via the NetworkGenesis CR. The operator reconciles it into roster and address book ConfigMaps.

### Acceptance Criteria
- [ ] NetworkGenesis CR created during fresh install
- [ ] Step waits for genesis completion before reporting success
- [ ] Idempotent — skips if already exists
- [ ] Rollback: delete NetworkGenesis if created by this step