style(storage,workspace): satisfy the repository lint gate

eslint --fix formatting sweep plus the manual residue: sync method
bodies drop async behind Promise-returning signatures (the sqlite unit
routes primitives through a settle() guard preserving the never-throws-
synchronously contract), catch callbacks type their reason as unknown,
loadAll's global slot is plain unknown (null semantics stay in JSDoc),
a non-null assertion becomes a narrowing, and unsafe any assignments in
tests gain explicit types. One justified eslint-disable for
prefer-promise-reject-errors follows the core/session precedent —
wrapping would discard the original StorageError code.

packages/storage/domain/tests/helpers/memory-backend.ts

@@ -18,10 +18,10 @@
 import { StorageError } from '@deepseek-ai/dsh-storage'
 import type { KvFacet, KvUnit, KvUnitDescriptor, StorageBackend } from '@deepseek-ai/dsh-storage'
 
-/** One unit's medium: tables of records plus the global slot. */
+/** One unit's medium: tables of records plus the global slot (`null` = never written). */
 export interface MemoryMedium {
   tables: Map<string, Map<string, unknown>>
-  global: unknown | null
+  global: unknown
 }
 
 /**
@@ -70,7 +70,7 @@ class MemoryKvUnit implements KvUnit {
     }
   }
 
-  async loadAll(): Promise<{ tables: Record<string, Record<string, unknown>>; global: unknown | null }> {
+  async loadAll(): Promise<{ tables: Record<string, Record<string, unknown>>; global: unknown }> {
     this.assertOpen()
     const tables: Record<string, Record<string, unknown>> = {}
     for (const table of this.descriptor.tables) {