refactor: create index.js for aql directory (#68)

packages/loot-core/bin/profile-sql.js

packages/loot-core/bin/sql-regenerate-views

packages/loot-core/src/mocks/arbitrary-schema.js

packages/loot-core/src/mocks/budget.js

packages/loot-core/src/server/accounts/export-to-csv.js

packages/loot-core/src/server/accounts/transaction-rules.js

...s/loot-core/src/server/accounts/transaction-rules.test.js

packages/loot-core/src/server/api.js

packages/loot-core/src/server/aql/index.js

packages/loot-core/src/server/db/index.js

packages/loot-core/src/server/main.js

packages/loot-core/src/server/schedules/app.js

packages/loot-core/src/server/schedules/app.test.js

packages/loot-core/src/server/schedules/find-schedules.js

packages/loot-core/src/server/spreadsheet/spreadsheet.js

packages/loot-core/src/server/sync/migrate.test.js

packages/loot-core/src/server/update.js