feat: macro regime + 30 historical events + regime confidence fix

- Add macro_regime (goldilocks/stagflation/recession/etc.) to every instrument snapshot via get_macro_gauges() + score_macro_scenarios()
- RegimeCard now shows global macro cycle section (emoji + label + top-3 scenarios) above technical signals
- Fix _detect_regime() confidence: capped at 85% max; add late-bull (dist_MA200 > 20%) and correction-in-bull (MA50 > MA200 but momentum < -3%) detection so regime no longer locks at 100%
- Add macro_events_bootstrap.py with 30 curated historical events (FOMC 2022-2025, CPI surprises, Ukraine/Hamas/Iran geopolitics, BOJ pivots, Bitcoin ETF, Liberation Day tariffs, SVB crisis, etc.)
- POST /api/timeline/bootstrap-macro endpoint (idempotent, deduplicates by name)
- Fix event date filter in _get_relevant_events(): overlap logic instead of start-only filter — events extending into the chart window are now included
- EventTimelineStrip: add "Signaux Techniques" fallback row for events not matched by any driver keyword (MA crossovers are now always visible)

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

backend/routers/timeline.py

@@ -155,6 +155,21 @@ FORMAT JSON STRICT:
         raise HTTPException(500, str(e))
 
 
+@router.post("/bootstrap-macro")
+def bootstrap_macro(force: bool = False) -> Dict[str, Any]:
+    """
+    Seed the market_events table with predefined historical macro + geopolitical events.
+    Pass ?force=true to re-run even if events already exist.
+    """
+    try:
+        from services.macro_events_bootstrap import bootstrap_macro_events
+        result = bootstrap_macro_events(force=force)
+        return result
+    except Exception as e:
+        logger.error(f"[Timeline] bootstrap_macro failed: {e}")
+        raise HTTPException(500, str(e))
+
+
 @router.get("/day/{ref_date}")
 def get_day_context(ref_date: str) -> Dict[str, Any]:
     from services.database import get_events_for_date, get_timeline_context