feat: add Hermes frontend types, API layer, and hooks (Phase 7)

- Add "hermes" to AppId union type and all exhaustive Record<AppId>
- Add HermesModelConfig, HermesAgentConfig, HermesEnvConfig types
- Add hermes field to VisibleApps, McpApps, ProxyTakeoverStatus
- Create src/lib/api/hermes.ts with Tauri invoke wrappers
- Create src/hooks/useHermes.ts with 5 query + 3 mutation hooks
- Register hermes in APP_IDS, APP_ICON_MAP (violet color scheme)
- Split MCP_SKILLS_APP_IDS into MCP_APP_IDS (includes hermes) and
  SKILLS_APP_IDS (excludes hermes, since Hermes has no Skills support)
- Wire hermes additive-mode into App.tsx (remove/duplicate handlers),
  ProviderList.tsx (live provider ID query + In Config badge),
  mutations.ts (cache invalidation on switch/add/delete)
- Add Hermes checkbox to McpFormModal
- Add basic hermes i18n keys (en/zh/ja)

src/hooks/useHermes.ts

@@ -0,0 +1,131 @@
+import { useMutation, useQuery, useQueryClient } from "@tanstack/react-query";
+import { hermesApi } from "@/lib/api/hermes";
+import { providersApi } from "@/lib/api/providers";
+import type {
+  HermesEnvConfig,
+  HermesAgentConfig,
+  HermesModelConfig,
+} from "@/types";
+
+/**
+ * Centralized query keys for all Hermes-related queries.
+ * Import this from any file that needs to invalidate Hermes caches.
+ */
+export const hermesKeys = {
+  all: ["hermes"] as const,
+  liveProviderIds: ["hermes", "liveProviderIds"] as const,
+  modelConfig: ["hermes", "modelConfig"] as const,
+  agentConfig: ["hermes", "agentConfig"] as const,
+  env: ["hermes", "env"] as const,
+  health: ["hermes", "health"] as const,
+};
+
+// ============================================================
+// Query hooks
+// ============================================================
+
+/**
+ * Query live provider IDs from Hermes config.
+ * Used by ProviderList to show "In Config" badge.
+ */
+export function useHermesLiveProviderIds(enabled: boolean) {
+  return useQuery({
+    queryKey: hermesKeys.liveProviderIds,
+    queryFn: () => providersApi.getHermesLiveProviderIds(),
+    enabled,
+  });
+}
+
+/**
+ * Query model configuration.
+ */
+export function useHermesModelConfig(enabled: boolean) {
+  return useQuery({
+    queryKey: hermesKeys.modelConfig,
+    queryFn: () => hermesApi.getModelConfig(),
+    enabled,
+  });
+}
+
+/**
+ * Query agent configuration.
+ */
+export function useHermesAgentConfig() {
+  return useQuery({
+    queryKey: hermesKeys.agentConfig,
+    queryFn: () => hermesApi.getAgentConfig(),
+    staleTime: 30_000,
+  });
+}
+
+/**
+ * Query env configuration.
+ */
+export function useHermesEnv() {
+  return useQuery({
+    queryKey: hermesKeys.env,
+    queryFn: () => hermesApi.getEnv(),
+    staleTime: 30_000,
+  });
+}
+
+/**
+ * Query config health warnings.
+ */
+export function useHermesHealth(enabled: boolean) {
+  return useQuery({
+    queryKey: hermesKeys.health,
+    queryFn: () => hermesApi.scanHealth(),
+    staleTime: 30_000,
+    enabled,
+  });
+}
+
+// ============================================================
+// Mutation hooks
+// ============================================================
+
+/**
+ * Save model config. Invalidates modelConfig and health queries on success.
+ * Toast notifications are handled by the component.
+ */
+export function useSaveHermesModelConfig() {
+  const queryClient = useQueryClient();
+  return useMutation({
+    mutationFn: (config: HermesModelConfig) => hermesApi.setModelConfig(config),
+    onSuccess: () => {
+      queryClient.invalidateQueries({ queryKey: hermesKeys.modelConfig });
+      queryClient.invalidateQueries({ queryKey: hermesKeys.health });
+    },
+  });
+}
+
+/**
+ * Save agent config. Invalidates agentConfig and health queries on success.
+ * Toast notifications are handled by the component.
+ */
+export function useSaveHermesAgentConfig() {
+  const queryClient = useQueryClient();
+  return useMutation({
+    mutationFn: (config: HermesAgentConfig) => hermesApi.setAgentConfig(config),
+    onSuccess: () => {
+      queryClient.invalidateQueries({ queryKey: hermesKeys.agentConfig });
+      queryClient.invalidateQueries({ queryKey: hermesKeys.health });
+    },
+  });
+}
+
+/**
+ * Save env config. Invalidates env and health queries on success.
+ * Toast notifications are handled by the component.
+ */
+export function useSaveHermesEnv() {
+  const queryClient = useQueryClient();
+  return useMutation({
+    mutationFn: (env: HermesEnvConfig) => hermesApi.setEnv(env),
+    onSuccess: () => {
+      queryClient.invalidateQueries({ queryKey: hermesKeys.env });
+      queryClient.invalidateQueries({ queryKey: hermesKeys.health });
+    },
+  });
+}