Introduce adapter injection and migrate test suite

Replace direct adapter/persistence imports with context-based injection
(AdapterContext + useAdapters) so tests use in-memory implementations
instead of vi.mock. Migrate component tests from context mocking to
AllProviders with real hooks. Extract export/import logic from ActionBar
into useEncounterExportImport hook. Add bestiary-cache and
bestiary-index-adapter test suites. Raise adapter coverage thresholds
(68→80 lines, 56→62 branches).

77 test files, 891 tests, all passing.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

apps/web/src/__tests__/adapters/in-memory-adapters.ts

@@ -0,0 +1,108 @@
+import {
+	type Creature,
+	type CreatureId,
+	EMPTY_UNDO_REDO_STATE,
+	type Encounter,
+	type PlayerCharacter,
+	type UndoRedoState,
+} from "@initiative/domain";
+import type { Adapters } from "../../contexts/adapter-context.js";
+
+export function createTestAdapters(options?: {
+	encounter?: Encounter | null;
+	undoRedoState?: UndoRedoState;
+	playerCharacters?: PlayerCharacter[];
+	creatures?: Map<CreatureId, Creature>;
+	sources?: Map<
+		string,
+		{ displayName: string; creatures: Creature[]; cachedAt: number }
+	>;
+}): Adapters {
+	let storedEncounter = options?.encounter ?? null;
+	let storedUndoRedo = options?.undoRedoState ?? EMPTY_UNDO_REDO_STATE;
+	let storedPCs = options?.playerCharacters ?? [];
+	const sourceStore =
+		options?.sources ??
+		new Map<
+			string,
+			{ displayName: string; creatures: Creature[]; cachedAt: number }
+		>();
+
+	// Pre-populate sourceStore from creatures map if provided
+	if (options?.creatures && !options?.sources) {
+		// No-op: creatures are accessed directly from the map
+	}
+
+	const creatureMap = options?.creatures ?? new Map<CreatureId, Creature>();
+
+	return {
+		encounterPersistence: {
+			load: () => storedEncounter,
+			save: (e) => {
+				storedEncounter = e;
+			},
+		},
+		undoRedoPersistence: {
+			load: () => storedUndoRedo,
+			save: (state) => {
+				storedUndoRedo = state;
+			},
+		},
+		playerCharacterPersistence: {
+			load: () => [...storedPCs],
+			save: (pcs) => {
+				storedPCs = pcs;
+			},
+		},
+		bestiaryCache: {
+			cacheSource(sourceCode, displayName, creatures) {
+				sourceStore.set(sourceCode, {
+					displayName,
+					creatures,
+					cachedAt: Date.now(),
+				});
+				for (const c of creatures) {
+					creatureMap.set(c.id, c);
+				}
+				return Promise.resolve();
+			},
+			isSourceCached(sourceCode) {
+				return Promise.resolve(sourceStore.has(sourceCode));
+			},
+			getCachedSources() {
+				return Promise.resolve(
+					[...sourceStore.entries()].map(([sourceCode, info]) => ({
+						sourceCode,
+						displayName: info.displayName,
+						creatureCount: info.creatures.length,
+						cachedAt: info.cachedAt,
+					})),
+				);
+			},
+			clearSource(sourceCode) {
+				sourceStore.delete(sourceCode);
+				return Promise.resolve();
+			},
+			clearAll() {
+				sourceStore.clear();
+				return Promise.resolve();
+			},
+			loadAllCachedCreatures() {
+				return Promise.resolve(new Map(creatureMap));
+			},
+		},
+		bestiaryIndex: {
+			loadIndex: () => ({ sources: {}, creatures: [] }),
+			getAllSourceCodes: () => [],
+			getDefaultFetchUrl: (sourceCode, baseUrl) => {
+				const filename = `bestiary-${sourceCode.toLowerCase()}.json`;
+				if (baseUrl !== undefined) {
+					const normalized = baseUrl.endsWith("/") ? baseUrl : `${baseUrl}/`;
+					return `${normalized}${filename}`;
+				}
+				return `https://example.com/${filename}`;
+			},
+			getSourceDisplayName: (sourceCode) => sourceCode,
+		},
+	};
+}