fix: alembic migrations (#470)

* fix: alembic migrations

This commit fixes all the migrations that was half-backed, due to auto
creation in the db init before. The process was to checkout at the
commit where the migration was created, and use --autogenerate to
regenerate at the state of the migration. 4 migrations was fixed.

It also includes a workflow to ensure migration can applies correctly.

* fix: db migration check

* fix: nullable on meeting_consent

* fix: try fixing tests

.github/workflows/db_migrations.yml

@@ -0,0 +1,55 @@
+name: Test Database Migrations
+
+on:
+  push:
+    paths:
+      - "server/migrations/**"
+      - "server/reflector/db/**"
+      - "server/alembic.ini"
+      - ".github/workflows/db_migrations.yml"
+  pull_request:
+    paths:
+      - "server/migrations/**"
+      - "server/reflector/db/**"
+      - "server/alembic.ini"
+      - ".github/workflows/db_migrations.yml"
+
+jobs:
+  test-migrations:
+    runs-on: ubuntu-latest
+
+    steps:
+      - uses: actions/checkout@v4
+
+      - name: Install poetry
+        run: pipx install poetry
+
+      - name: Set up Python 3.x
+        uses: actions/setup-python@v4
+        with:
+          python-version: "3.11"
+          cache: "poetry"
+          cache-dependency-path: "server/poetry.lock"
+
+      - name: Install requirements
+        working-directory: ./server
+        run: |
+          poetry install --no-root
+
+      - name: Test migrations from scratch
+        working-directory: ./server
+        run: |
+          echo "Testing migrations from clean database..."
+          poetry run alembic upgrade head
+          echo "✅ Fresh migration successful"
+
+      - name: Test migration rollback and re-apply
+        working-directory: ./server
+        run: |
+          echo "Testing rollback to base..."
+          poetry run alembic downgrade base
+          echo "✅ Rollback successful"
+
+          echo "Testing re-apply of all migrations..."
+          poetry run alembic upgrade head
+          echo "✅ Re-apply successful"