phase G: data minimisation + passwordless auth + DeepSeek-first LLM

Server no longer holds portfolios. Holdings live in the browser
(localStorage); the server publishes an anonymous ticker_universe and a
gzipped /api/universe payload identical for every authenticated user, so
access patterns can't betray which tickers a user holds. AI commentary
is generated ephemerally from the browser-supplied pie and the cost
ledger row records no positions. Migrations 0009-0011 added the
universe table and dropped positions / portfolio_snapshots /
portfolios.

Authentication is now e-mail OTP only. Migration 0010 dropped
password_hash and email_verified (every active session is by
construction proof of email control). The /signup endpoint is gone;
signup and login share a single email-entry page. Email rendering is
HTML+plain-text multipart with a shared brand palette (app/branding.py)
asserted in sync with the CSS by a drift-detection test.

LLM provider defaults to DeepSeek-direct (cheaper, api.deepseek.com)
with OpenRouter as automatic fallback if DeepSeek fails. ai_log_job and
indicator_summary_job now iterate the two tones (NOVICE, INTERMEDIATE)
per cycle so the dashboard's tone toggle is instant; PROMPT_VERSION
bumped to 6 with an educational anti-TA / anti-gambling stance baked
into _CORE. NOVICE mode renders a curated glossary inline (CBOE VIX,
yield curve, HY OAS, etc.) with JS-positioned tooltips that survive
viewport edges and sticky bars. Model name and tokens hidden from the
user UI; still recorded in StrategicLog.model and AICall for admin.

Layout adds a sticky top nav, a sticky bottom markets bar (one chip per
exchange with status LED + headline index + 1d change), and
Phase H feedback reporting is queued in tasks/todo.md.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

app/redis_client.py

@@ -0,0 +1,39 @@
+"""Shared async Redis client.
+
+Redis is used as scratch / cache only — never as a system of record. We
+disable RDB/AOF in compose so a restart wipes state, which matches the
+"ephemeral pie" property: anything the server temporarily holds during
+/api/analyze or /api/portfolio/parse must not survive a restart.
+
+The client is module-singleton; FastAPI handlers get it via get_redis()."""
+from __future__ import annotations
+
+from typing import Optional
+
+import redis.asyncio as redis
+
+from app.config import get_settings
+
+
+_client: Optional[redis.Redis] = None
+
+
+def get_redis() -> redis.Redis:
+    global _client
+    if _client is None:
+        s = get_settings()
+        _client = redis.from_url(
+            s.REDIS_URL,
+            encoding="utf-8",
+            decode_responses=True,
+            socket_timeout=5,
+            socket_connect_timeout=5,
+        )
+    return _client
+
+
+async def close_redis() -> None:
+    global _client
+    if _client is not None:
+        await _client.aclose()
+        _client = None