fix: properly detect flags after -link and -date

Previously, /edit 28 -link -date would treat -date as the link value.
Now it checks if the next argument starts with "-" to detect flags.

apps/telegram-bot/commands.py

@@ -106,14 +106,14 @@ def parse_args(
         arg = args[i]
 
         if arg == "-link":
-            if i + 1 < len(args):
+            if i + 1 < len(args) and not args[i + 1].startswith("-"):
                 link = args[i + 1]
                 i += 2
             else:
                 clear_link = True
                 i += 1
         elif arg == "-date":
-            if i + 1 < len(args):
+            if i + 1 < len(args) and not args[i + 1].startswith("-"):
                 due_date_ts = parse_date_with_tz(args[i + 1])
                 if due_date_ts is not None:
                     i += 2