Remove unused components and models for improved maintainability

- Deleted redundant components (`AddActionButton`, `AlertBox`, `AlertStack`, `BackButton`, `CancelButton`, and `CollapsableArea`) and related files.
- Removed unused models (`Book`, `BookSerie`, `BookTables`, `Character`, and `Chapter`) to reduce codebase clutter.
- Updated project structure and references to reflect these removals.

lib/constants/spell.ts

@@ -0,0 +1,35 @@
+import {SelectBoxProps} from "@/components/form/SelectBox";
+import {SpellEditState} from "@/lib/types/spell";
+
+export const initialSpellState: SpellEditState = {
+    id: null,
+    name: '',
+    description: '',
+    appearance: '',
+    tags: [],
+    powerLevel: null,
+    components: null,
+    limitations: null,
+    notes: null,
+    seriesSpellId: null,
+};
+
+export const spellPowerLevels: SelectBoxProps[] = [
+    {value: 'none', label: 'spellPowerLevels.none'},
+    {value: 'cantrip', label: 'spellPowerLevels.cantrip'},
+    {value: 'novice', label: 'spellPowerLevels.novice'},
+    {value: 'apprentice', label: 'spellPowerLevels.apprentice'},
+    {value: 'journeyman', label: 'spellPowerLevels.journeyman'},
+    {value: 'expert', label: 'spellPowerLevels.expert'},
+    {value: 'master', label: 'spellPowerLevels.master'},
+    {value: 'grandmaster', label: 'spellPowerLevels.grandmaster'},
+    {value: 'legendary', label: 'spellPowerLevels.legendary'},
+    {value: 'divine', label: 'spellPowerLevels.divine'},
+];
+
+export const defaultTagColors: string[] = [
+    '#51AE84', '#3A8B69', '#2196F3', '#1976D2',
+    '#FFA726', '#FF9800', '#EF5350', '#E53935',
+    '#AB47BC', '#9C27B0', '#26A69A', '#00897B',
+    '#5C6BC0', '#3F51B5', '#EC407A', '#D81B60',
+];