docs: the submit check cannot reliably recognise a multi-line paste

It does match one Claude shows inline when the first line has 24+
non-space characters; it misses a short first line and the
[Pasted text #N +k lines] placeholder. Say "cannot reliably" instead of
"cannot".

Co-Authored-By: Christian Haberl <116439789+christianhaberl@users.noreply.github.com>
Co-Authored-By: Claude <noreply@anthropic.com>

docs/wiki/Cron-Jobs.md

@@ -52,9 +52,9 @@ or a server restart shifts later runs slightly. That drift is accepted rather th
 ## Prompts are single line
 
 This is the rule people trip over. A cron job fires with nobody watching, and the check that
-re-presses an Enter the agent ignored cannot recognise a multi-line paste in the composer, so
-a multi-line prompt could sit there unsent. In `paste` mode the newlines would reach the agent
-as keys. So a multi-line prompt is **rejected**: the form refuses it, and a prompt file whose
+re-presses an Enter the agent ignored cannot reliably recognise a multi-line paste in the
+composer, so a multi-line prompt could sit there unsent. In `paste` mode the newlines would
+reach the agent as keys. So a multi-line prompt is **rejected**: the form refuses it, and a prompt file whose
 contents are multi-line fails the run with a clear message.
 
 For anything longer than a sentence, put the instructions in a file and make the prompt tell