fix(db): move share-aliases migration spec out of migrations/

The #205 share-aliases feature placed share-aliases.migration.spec.ts
inside src/database/migrations/. Kysely's FileMigrationProvider loads
EVERY file in that folder as a migration, so `migration:latest` imported
the test file and crashed with "ReferenceError: describe is not defined"
(no Jest globals under tsx). That broke the migration step shared by the
e2e-server, e2e-mcp and integration-test (test/test) jobs.

Move the spec one level up to src/database/ (matching the existing
src/database/jsonb-bind.spec.ts convention) so the migration runner no
longer sees it, and fix its relative imports
(./migrations/... and ./types/...). Jest still picks it up via the
src/**/*.spec.ts test glob. Verified locally: 3 passed.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

apps/server/src/database/share-aliases.migration.spec.ts

@@ -1,9 +1,9 @@
-import * as migration from './20260626T130000-share-aliases';
+import * as migration from './migrations/20260626T130000-share-aliases';
 import type {
   InsertableShareAlias,
   ShareAlias,
   UpdatableShareAlias,
-} from '../types/entity.types';
+} from './types/entity.types';
 
 /**
  * Sanity checks for the share_aliases migration + entity types. We don't run a