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/config.py

@@ -28,6 +28,14 @@ Environment variables:
                                  X-Gitea-Signature HMAC is enforced.
     KANBANTE_SYNC_LABELS         "1" (default) = mirror intermediate
                                  columns to Gitea labels named kanban:<col>.
+    KANBANTE_NTFY_URL            Base URL of an ntfy server (e.g.
+                                 https://ntfy.sh or self-hosted).
+    KANBANTE_NTFY_TOPIC          ntfy topic for the daily briefing.
+    KANBANTE_NTFY_TOKEN          Optional Bearer token for ntfy.
+    KANBANTE_BRIEFING_TIME       "HH:MM" (server local time) at which
+                                 the daily briefing is sent to ntfy.
+                                 Empty (default) = no automatic send,
+                                 the /briefing page stays available.
 """
 
 import os
@@ -36,7 +44,7 @@ from pathlib import Path
 
 BASE_DIR = Path(__file__).resolve().parent.parent
 
-APP_VERSION = "0.4.0"
+APP_VERSION = "0.5.0"
 
 
 def _env_bool(name: str, default: bool) -> bool:
@@ -88,6 +96,10 @@ class Settings:
     aging_days: int = 7
     webhook_secret: str = ""
     sync_labels: bool = True
+    ntfy_url: str = ""
+    ntfy_topic: str = ""
+    ntfy_token: str = ""
+    briefing_time: str = ""
 
     @property
     def auth_enabled(self) -> bool:
@@ -113,4 +125,8 @@ def get_settings() -> Settings:
         aging_days=_env_int("KANBANTE_AGING_DAYS", 7),
         webhook_secret=os.getenv("KANBANTE_WEBHOOK_SECRET", ""),
         sync_labels=_env_bool("KANBANTE_SYNC_LABELS", True),
+        ntfy_url=os.getenv("KANBANTE_NTFY_URL", ""),
+        ntfy_topic=os.getenv("KANBANTE_NTFY_TOPIC", ""),
+        ntfy_token=os.getenv("KANBANTE_NTFY_TOKEN", ""),
+        briefing_time=os.getenv("KANBANTE_BRIEFING_TIME", ""),
     )