The provisioner's client fills a handed module's file but for each `${secret:<provision>}` (or a whole `secrets` file
that is the placeholder alone).
- The node-engine reads the provision's key `<node>.<consumer>.<provision>[.<local>]` in mesh-provisioner's
`provisions`. The key must be `provided` and carry the vault's reference.
- It asks the vault's `own` for that pair credential sealed to this machine, at least at the reference's generation,
and opens it with the node's sealing key.
- It writes the file as declared (its owner), 0600 when the declaration gives no mode.
- Anything short of that refuses the write, naming the provision and why.
A module the node composes itself already has its `secrets` files written so: its composition carries the vault's
value from `own`, written 0600 with the declared owner.
Pins mesh-sdk 4a96793 (go/provisions). Tests: rows in TestAWriteAndAnApplyOfTheSameFileSerialise.
jschoubben
6b32e07164