Add reset option to /incidents_diff

handlers/system.py

@@ -399,11 +399,19 @@ async def incidents_diff(msg: Message):
         return
     parts = msg.text.split()
     hours = 24
+    reset = False
     if len(parts) >= 2:
+        if parts[1].lower() in {"reset", "clear"}:
+            reset = True
+        else:
             try:
                 hours = max(1, int(parts[1]))
             except ValueError:
                 hours = 24
+    if reset:
+        runtime_state.set_state("incidents_diff_last_ts", None)
+        await msg.answer("📣 Diff marker reset. Next run will show all within window.", reply_markup=system_logs_audit_kb)
+        return
     last_iso = runtime_state.get("incidents_diff_last_ts")
     last_dt = None
     if isinstance(last_iso, str):