Initial AlphaPulse implementation: news crawler and Binance klines

- Backend (FastAPI, SQLAlchemy 2, Alembic): single-admin cookie auth,
  news/crawler/market APIs with SSE and WebSocket streaming
- Crawler (Scrapy + Scrapy-Redis): wscn_news, wscn_live, cls_depth,
  cls_telegraph spiders, idempotent upserts with revisions, raw response
  archiving, per-source subprocess supervision, restart and backoff
- Market worker: full-history Binance spot/USD-M kline backfill,
  realtime WS stream, hourly and on-reconnect catch-up
- Frontend (Vue 3, Element Plus, UnoCSS, KLineChart): news feed,
  crawler console with live logs, Binance-style chart page
- Deploy: docker compose, nginx site, migrate and daily backup scripts

backend/alembic/script.py.mako

@@ -0,0 +1,28 @@
+"""${message}
+
+Revision ID: ${up_revision}
+Revises: ${down_revision | comma,n}
+Create Date: ${create_date}
+
+"""
+from typing import Sequence, Union
+
+from alembic import op
+import sqlalchemy as sa
+${imports if imports else ""}
+
+# revision identifiers, used by Alembic.
+revision: str = ${repr(up_revision)}
+down_revision: Union[str, Sequence[str], None] = ${repr(down_revision)}
+branch_labels: Union[str, Sequence[str], None] = ${repr(branch_labels)}
+depends_on: Union[str, Sequence[str], None] = ${repr(depends_on)}
+
+
+def upgrade() -> None:
+    """Upgrade schema."""
+    ${upgrades if upgrades else "pass"}
+
+
+def downgrade() -> None:
+    """Downgrade schema."""
+    ${downgrades if downgrades else "pass"}