signal_log: persist agent panel verdict + per-persona takes to SQLite

Add panel_verdict, panel_confidence, panel_rationale, panel_takes_json
columns to the signals table (additive, idempotent ALTER TABLE migration
for existing DBs). _report_row now reads the panel fields attach_panel
writes onto the SignalReport, so LLM panel verdicts stop evaporating on
process exit. Also documents the Oanda re-pin (round_trip_cost stays
$0.30 for cross-book comparability and the live TP gate; $0.65 is the
measured headline) and adds the feed-divergence / parity / shadow-scan
study tooling referenced by CLAUDE.md.

docs/user_guide.html

@@ -84,16 +84,16 @@
 </ol>
 
 <h2>4 · Choosing your timeframe</h2>
-<p>Twelve-month backtest (Jul 2025 – Jul 2026, real spreads, entry at next candle open):</p>
+<p>Twelve-month Oanda-candle backtest (Aug 2025 – Aug 2026, $0.65 round-trip cost, entry at next candle open):</p>
 <table>
 <tr><th></th><th>M5</th><th>M15</th><th>H1</th></tr>
-<tr><td>Trades / week</td><td>~10</td><td>~9.5</td><td>~3</td></tr>
-<tr><td>Total result (12 mo)</td><td>+135.6R</td><td>+67.2R</td><td>+49.9R</td></tr>
-<tr><td>Win rate / profit factor</td><td>59.7% / 1.81</td><td>55.8% / 1.40</td><td>59.4% / 1.94</td></tr>
-<tr><td>Typical (median) hold</td><td>2.4 h</td><td>6 h</td><td>12.5 h</td></tr>
-<tr><td>90% of trades close within</td><td>16 h</td><td>40 h</td><td>3.7 days</td></tr>
-<tr><td>Typical stop distance</td><td>~$19</td><td>~$29</td><td>~$44</td></tr>
-<tr><td>Worst drawdown</td><td>11.2R</td><td>9.4R</td><td>9.5R</td></tr>
+<tr><td>Trades / week</td><td>~11.3</td><td>~7.6</td><td>~2.7</td></tr>
+<tr><td>Total result (12 mo)</td><td>+106.8R</td><td>+73.9R</td><td>+24.0R</td></tr>
+<tr><td>Win rate / profit factor</td><td>52.9% / 1.51</td><td>62.2% / 1.53</td><td>60.9% / 1.55</td></tr>
+<tr><td>Typical (median) hold</td><td>2.4 h</td><td>7 h</td><td>15.5 h</td></tr>
+<tr><td>90% of trades close within</td><td>10.5 h</td><td>29.8 h</td><td>3.2 days</td></tr>
+<tr><td>Typical stop distance</td><td>~$21</td><td>~$32</td><td>~$52</td></tr>
+<tr><td>Worst drawdown</td><td>10.7R</td><td>10.8R</td><td>8.0R</td></tr>
 </table>
 <ul>
 <li><b>M5 — intraday, execution-critical.</b> Highest total edge, but stops are tight: a couple of dollars of slippage or a late entry eats a meaningful share of every trade. Suitable only if you can act within a minute or two of the alert (or automate). Trades open and close within a session; you sleep flat.</li>
@@ -104,7 +104,7 @@
 
 <h2>5 · What to expect (and what not to)</h2>
 <ul>
-<li><b>You will lose ~40% of trades.</b> A 56–60% win rate means losing streaks of 5+ are routine over a year. The system's edge is the average across hundreds of trades, not any single one.</li>
+<li><b>You will lose roughly 38–47% of trades.</b> A 53–62% win rate means losing streaks of 5+ are routine over a year. The system's edge is the average across hundreds of trades, not any single one.</li>
 <li><b>Stops hit fast, winners take time.</b> Losing trades die in roughly half the time winners take. An early stop-out is the system doing its job.</li>
 <li><b>Drawdowns of ~10R are normal.</b> At 1% risk per trade, expect to be ~10% down from a peak at some point in a normal year. This is why risking more than 1% per trade is how accounts die.</li>
 <li><b>Backtest ≠ live.</b> Results above charge real spreads and realistic fills, but cannot model your personal latency, broker slippage, or requotes. Assume live results will be somewhat worse — especially on M5.</li>