feat(palier-3): recherche globale, mes issues, briefing ntfy, MCP lecture

- client: search_issues (/repos/issues/search, type=issues,
  assigned_by), delete_label + forget_label_cache; models: kv_store
- /search groupe par projet avec colonne Kanban; /my = issues
  ouvertes assignées à l'utilisateur du jeton (get_user)
- briefing: _briefing_data (focus, âgées, milestones <= 7 j,
  activité journal), page /briefing, /api/briefing, envoi ntfy
  manuel + planificateur lifespan à KANBANTE_BRIEFING_TIME
  (kv briefing_last_sent, pas de doublon); app/briefing.py =
  format texte + envoi ntfy (en-têtes ASCII)
- MCP: POST /mcp JSON-RPC (initialize, tools/list, tools/call,
  ping, notifications 202), 7 outils en lecture seule, GET /mcp
  de découverte; erreurs -32601/-32700, isError pour les outils
- focus refactoré en _collect_focus_groups réutilisé par le
  briefing et l'outil MCP get_focus

app/briefing.py

@@ -0,0 +1,71 @@
+"""Daily briefing: formatting and ntfy delivery.
+
+The data itself is gathered in app.main (it needs the board helpers);
+this module only turns it into a readable text and pushes it to an
+ntfy topic. Kept dependency-light so it is unit-testable alone.
+"""
+
+from __future__ import annotations
+
+import httpx
+
+from app.config import Settings
+
+
+def ntfy_configured(settings: Settings) -> bool:
+    return bool(settings.ntfy_url and settings.ntfy_topic)
+
+
+def format_briefing_text(data: dict) -> str:
+    """Plain-text briefing (ntfy body, also shown on /briefing)."""
+    lines: list[str] = [f"📋 Kanbante — briefing du {data['date']}"]
+    activity = data["activity_24h"]
+    lines.append(
+        f"\n⚡ Dernières 24 h : {activity['closed']} fermée(s), "
+        f"{activity['created']} créée(s), {activity['moved']} déplacement(s)."
+    )
+    if activity.get("avg_cycle_days") is not None:
+        lines.append(f"⏱️ Temps de cycle moyen (30 j) : {activity['avg_cycle_days']} j.")
+
+    lines.append(f"\n🎯 En cours / en révision : {data['focus_total']} carte(s)")
+    for group in data["focus_groups"][:6]:
+        lines.append(f"  • {group['full_name']} : {group['count']}")
+        for title in group["titles"][:3]:
+            lines.append(f"      – {title}")
+
+    if data["aging"]:
+        lines.append("\n⏳ Cartes qui vieillissent :")
+        for card in data["aging"][:8]:
+            lines.append(
+                f"  • {card['repo']} #{card['number']} « {card['title']} » "
+                f"— {card['days']} j en {card['column_label']}"
+            )
+
+    if data["milestones_due"]:
+        lines.append("\n📅 Milestones proches :")
+        for ms in data["milestones_due"][:5]:
+            lines.append(
+                f"  • {ms['repo']} « {ms['title']} » — échéance "
+                f"{ms['due_on']} ({ms['open']} ouverte(s))"
+            )
+
+    if data["focus_total"] == 0 and not data["aging"]:
+        lines.append("\n🎉 Rien d'urgent : aucun encours, aucune carte vieillissante.")
+    return "\n".join(lines)
+
+
+async def send_ntfy(settings: Settings, text: str) -> bool:
+    """POST the briefing to the configured ntfy topic. True on 2xx."""
+    if not ntfy_configured(settings):
+        return False
+    url = f"{settings.ntfy_url.rstrip('/')}/{settings.ntfy_topic}"
+    headers = {
+        # ntfy headers must stay ASCII; the body carries the accents.
+        "Title": "Kanbante - briefing du jour",
+        "Tags": "clipboard,chart_with_upwards_trend",
+    }
+    if settings.ntfy_token:
+        headers["Authorization"] = f"Bearer {settings.ntfy_token}"
+    async with httpx.AsyncClient(timeout=15.0) as client:
+        response = await client.post(url, content=text.encode("utf-8"), headers=headers)
+    return response.status_code < 300