Setup and migration UI refactor (#1190)

* Make config instance-based
* Remove config dependency in paths
* Refactor config init
* Allow startup without database
* Get system status at UI initialise
* Add setup wizard
* Cache and Metadata optional. Database mandatory
* Handle metadata not set during full import/export
* Add links
* Remove config check middleware
* Stash not mandatory
* Panic on missing mandatory config fields
* Redirect setup to main page if setup not required
* Add migration UI
* Remove unused stuff
* Move UI initialisation into App
* Don't create metadata paths on RefreshConfig
* Add folder selector for generated in setup
* Env variable to set and create config file.
Make docker images use a fixed config file.
* Set config file during setup

pkg/sqlite/transaction.go

@@ -29,6 +29,10 @@ func (t *transaction) Begin() error {
 		return errors.New("transaction already begun")
 	}
 
+	if err := database.Ready(); err != nil {
+		return err
+	}
+
 	var err error
 	t.tx, err = database.DB.BeginTxx(t.Ctx, nil)
 	if err != nil {
@@ -124,6 +128,10 @@ func (t *transaction) Tag() models.TagReaderWriter {
 type ReadTransaction struct{}
 
 func (t *ReadTransaction) Begin() error {
+	if err := database.Ready(); err != nil {
+		return err
+	}
+
 	return nil
 }