build: 打通 FastAPI 与 Vue 最小工程、依赖与数据库连接

后端入口、配置、Redis 与 Alembic 迁移就位；前端 Vite 工程可安装可构建。

backend/alembic/versions/add_faq_seo_fields.py

@@ -0,0 +1,27 @@
+"""Per-article SEO overrides on FAQs
+
+Revision ID: add_faq_seo_001
+Revises: rel_hc_uploads_001
+Create Date: 2026-07-25
+
+Adds nullable meta_title / meta_description to faqs so an org can override the
+public article page's <title> and meta description instead of always deriving
+them from the question and answer excerpt. NULL keeps today's derived behaviour.
+"""
+from alembic import op
+import sqlalchemy as sa
+
+revision = "add_faq_seo_001"
+down_revision = "rel_hc_uploads_001"
+branch_labels = None
+depends_on = None
+
+
+def upgrade() -> None:
+    op.add_column("faqs", sa.Column("meta_title", sa.String(length=120), nullable=True))
+    op.add_column("faqs", sa.Column("meta_description", sa.String(length=300), nullable=True))
+
+
+def downgrade() -> None:
+    op.drop_column("faqs", "meta_description")
+    op.drop_column("faqs", "meta_title")