Ref: refactor file structure, relocated settings storage to user appdata

[Ycyken]

1. Refactor file structure,
2. Relocated settings storage to user appdata
3. Fix bug in sqlite test
4. A little preparing for app release

[github-actions]

Code Coverage

File	Coverage [12.96%]
src/main/kotlin/model/graph/Graph.kt	80.00%
src/main/kotlin/view/common/AddEdgeDialog.kt	0.00%
src/main/kotlin/view/common/AddVertexDialog.kt	0.00%
src/main/kotlin/view/common/DefaultButton.kt	0.00%
src/main/kotlin/view/common/DirectedAlgorithmDialog.kt	0.00%
src/main/kotlin/view/common/styling.kt	56.00%
src/main/kotlin/view/graph/GraphView.kt	0.00%
src/main/kotlin/view/graph/edge/DirectedEdgeView.kt	0.00%
src/main/kotlin/view/graph/edge/UndirectedEdgeView.kt	0.00%
src/main/kotlin/view/graph/vertex/DirectedVertexView.kt	0.00%
src/main/kotlin/view/graph/vertex/UndirectedVertexView.kt	0.00%
src/main/kotlin/view/screens/DirectedGraphScreen.kt	0.00%
src/main/kotlin/view/screens/MainScreen.kt	0.00%
src/main/kotlin/view/screens/UndirectedGraphScreen.kt	0.00%
src/main/kotlin/view/screens/settings/Language.kt	0.00%
src/main/kotlin/view/screens/settings/Localisation.kt	0.00%
src/main/kotlin/view/screens/settings/Saving.kt	0.00%
src/main/kotlin/view/screens/settings/SettingsScreen.kt	52.94%
src/main/kotlin/viewmodel/MainScreenViewModel.kt	39.73%
src/main/kotlin/viewmodel/graph/AbstractGraphViewModel.kt	31.75%
src/main/kotlin/viewmodel/graph/DirectedGraphViewModel.kt	25.00%
src/main/kotlin/viewmodel/graph/EdgeViewModel.kt	100.00%
src/main/kotlin/viewmodel/graph/UndirectedGraphViewModel.kt	0.00%
src/main/kotlin/viewmodel/io/Neo4jRepository.kt	0.00%
src/main/kotlin/viewmodel/io/SQLiteRepository.kt	46.43%

Total Project Coverage	22.87%