feat: serve all precached data offline via DataCache fallback

- DataCache.fetchWithFallback: network-first with IDB write-through under
  the same url: keys the preload writes; falls back to precached IDB copy
  when offline — closes the preload(IDB) vs read(SW cache) gap that made
  the Bible reader (and every other view) fail offline despite precaching
- Convert all 33 raw /data fetches across bible/service/menaion/prayer/
  calendar/settings views; in-memory caches and notFound maps preserved
- fetchCommandText: switch to lowercase services/commands/ (already in
  preload manifest); tolerate both TEXT/text node casings per migrate-data
- Remove stale duplicate static/data/en/services/Command/ (15 files)
- fetchLives: fix misc fallback to real lives/misc/{N}.json bundles

src/ui/prayer-view.ts

@@ -8,6 +8,7 @@ import { assembleService, type ServiceContext } from '../core/service-assembler'
 import type { EvalContext, ServiceNode } from '../core/types';
 import { getTranslations, type LanguageCode } from '../core/i18n';
 import { loadSettings, fontClass } from './settings-view';
+import { DataCache } from '../core/data-cache';
 
 export type PrayerCollection = 'prayer-rule' | 'akathists' | 'parimii' | 'horologion' | 'sbornik' | 'paraclete' | 'irmologion' | 'triodion';
 
@@ -270,12 +271,11 @@ export class PrayerView {
         }
         dataPath = `/data/shared/services/paraclete/tone${m[1]}/${m[2]}.json`;
       }
-      const resp = await fetch(dataPath);
-      if (!resp.ok) {
+      const nodes = await DataCache.fetchWithFallback<ServiceNode[]>(dataPath);
+      if (!nodes) {
         contentEl.innerHTML = `<p class="text-navy-light">${this.t.prayer.notFound}</p>`;
         return;
       }
-      const nodes: ServiceNode[] = await resp.json();
 
       const evalCtx: EvalContext = {};
       const ctx: ServiceContext = {