refactor(db): move ocr provider schema to root schemas directory

The ocr provider schema was moved from `schemas/ocr/provider.ts` to `schemas/ocrProvider.ts` to simplify the directory structure and make imports more straightforward. All related imports were updated accordingly.

src/main/data/db/schemas/index.ts

@@ -1,3 +1,3 @@
 export { appStateTable } from './appState'
-export { ocrProviderTable } from './ocr/provider'
+export { ocrProviderTable } from './ocrProvider'
 export { preferenceTable } from './preference'

src/main/data/db/schemas/ocrProvider.ts

@@ -1,7 +1,7 @@
 import type { OcrProviderCapabilityRecord, OcrProviderConfig } from '@types'
 import { index, sqliteTable, text } from 'drizzle-orm/sqlite-core'
 
-import { createUpdateTimestamps } from '../columnHelpers'
+import { createUpdateTimestamps } from './columnHelpers'
 
 export const ocrProviderTable = sqliteTable(
   'ocr_provider',

src/main/data/repositories/OcrProviderRepository.ts

@@ -1,5 +1,5 @@
 import { dbService } from '@data/db/DbService'
-import { ocrProviderTable } from '@data/db/schemas/ocr/provider'
+import { ocrProviderTable } from '@data/db/schemas/ocrProvider'
 import { loggerService } from '@logger'
 import type {
   DbOcrProvider,