internal/app: do not encode config early

Finalise no longer clobbers hst.Config.

Signed-off-by: Ophestra <cat@gensokyo.uk>

internal/app/state/state.go

@@ -3,12 +3,12 @@ package state
 
 import (
 	"errors"
-	"io"
 	"time"
 
 	"hakurei.app/hst"
 )
 
+// ErrNoConfig is returned by [Cursor] when used with a nil [hst.Config].
 var ErrNoConfig = errors.New("state does not contain config")
 
 type Entries map[ID]*State
@@ -27,23 +27,23 @@ type Store interface {
 	Close() error
 }
 
-// Cursor provides access to the store
+// Cursor provides access to the store of an identity.
 type Cursor interface {
-	Save(state *State, configWriter io.WriterTo) error
+	Save(state *State) error
 	Destroy(id ID) error
 	Load() (Entries, error)
 	Len() (int, error)
 }
 
-// State is an instance state
+// State is the on-disk state of a container instance.
 type State struct {
-	// hakurei instance id
+	// Unique instance id, generated by internal/app.
 	ID ID `json:"instance"`
-	// child process PID value
+	// Shim process pid. This runs as the target user.
 	PID int `json:"pid"`
-	// sealed app configuration
+	// Configuration value used to start the container.
 	Config *hst.Config `json:"config"`
 
-	// process start time
+	// Exact point in time that the shim process was created.
 	Time time.Time `json:"time"`
 }