core: api to save/get app settings to migrate them as part of the database (#3824)

* rfc: migrate app settings as part of export/import/migration

* export/import app settings

* test, fix

* chat: store app settings in db (#3834)

* chat: store app settings in db

* add combining with app-defaults

* commit schema

* test with tweaked settings

* remove unused error

---------

Co-authored-by: Evgeny Poberezkin <evgeny@poberezkin.com>

* remove app settings from export/import

* test, more settings

---------

Co-authored-by: Alexander Bondarenko <486682+dpwiz@users.noreply.github.com>

src/Simplex/Chat.hs

@@ -68,6 +68,7 @@ import Simplex.Chat.Protocol
 import Simplex.Chat.Remote
 import Simplex.Chat.Remote.Types
 import Simplex.Chat.Store
+import Simplex.Chat.Store.AppSettings
 import Simplex.Chat.Store.Connections
 import Simplex.Chat.Store.Direct
 import Simplex.Chat.Store.Files
@@ -597,6 +598,8 @@ processChatCommand' vr = \case
     fileErrs <- importArchive cfg
     setStoreChanged
     pure $ CRArchiveImported fileErrs
+  APISaveAppSettings as -> withStore' (`saveAppSettings` as) >> ok_
+  APIGetAppSettings platformDefaults -> CRAppSettings <$> withStore' (`getAppSettings` platformDefaults)
   APIDeleteStorage -> withStoreChanged deleteStorage
   APIStorageEncryption cfg -> withStoreChanged $ sqlCipherExport cfg
   TestStorageEncryption key -> sqlCipherTestKey key >> ok_
@@ -6469,6 +6472,8 @@ chatCommandP =
       "/db key " *> (APIStorageEncryption <$> (dbEncryptionConfig <$> dbKeyP <* A.space <*> dbKeyP)),
       "/db decrypt " *> (APIStorageEncryption . (`dbEncryptionConfig` "") <$> dbKeyP),
       "/db test key " *> (TestStorageEncryption <$> dbKeyP),
+      "/_save app settings" *> (APISaveAppSettings <$> jsonP),
+      "/_get app settings" *> (APIGetAppSettings <$> optional (A.space *> jsonP)),
       "/sql chat " *> (ExecChatStoreSQL <$> textP),
       "/sql agent " *> (ExecAgentStoreSQL <$> textP),
       "/sql slow" $> SlowSQLQueries,