fix(playbooks): 3.1.1 deploy — and why the markers match presence, not count

Deploys althing-core 3.1.1 to nh3-extdev. Both markers present on both
boxes; the warning verified behaviourally in four conditions rather than
by grep alone -- mismatched inherited handle warns, matching handle
silent, explicit --handle silent, unlaunched directory silent, and the
warning precedes the output it is about.

The release's own verification line says
`grep -c handles_launched_at dev_launch.py # 2+`. The real count there
is 1, the definition; the other two occurrences are in postbox.py. The
installed tree is byte-identical to the repo at the pushed tag, so the
instruction is wrong rather than the install.

This playbook matches on presence via grep -q, so it passed. Had it
asserted the stated count it would have reported FAILED on a perfect
deploy -- a verification instruction that fails on correct input, which
is the same false-negative this file has now produced three times in
different costumes. Recorded above the variable so the next bump does
not reintroduce a count.

playbooks/nh3-extdev-althing-v3.yaml

@@ -19,8 +19,8 @@
 # Rerunnable: a second run shows the install and unit steps skipped.
 
 vars:
-  wheel_src: /home/lkraven/development/althing/dist/althing_core-3.1.0-py3-none-any.whl
+  wheel_src: /home/lkraven/development/althing/dist/althing_core-3.1.1-py3-none-any.whl
-  wheel_dest: /tmp/althing_core-3.1.0-py3-none-any.whl
+  wheel_dest: /tmp/althing_core-3.1.1-py3-none-any.whl
   uv: /home/infra-ops/.local/bin/uv
   tool_dir: /opt/uv-tools
   bin_dir: /usr/local/bin
@@ -33,12 +33,18 @@ vars:
   #   3.0.1  zellij.py:_PANE_ID  session_source.py:_live_pid    (pane routes)
   #   3.0.3  post_office_herald.py:PANE_SETTLE_S               (write/submit race)
   #   3.1.0  post_office_herald.py:POST_OFFICE_HINT  dev_launch.py:resolve_post_office
-  markers: "post_office_herald.py:POST_OFFICE_HINT dev_launch.py:resolve_post_office"
+  #   3.1.1  postbox.py:warn_if_handle_looks_wrong    dev_launch.py:handles_launched_at
+  #
+  # ⚠ Match on PRESENCE (grep -q), never on a count. 3.1.1 shipped with a stated
+  # expectation of "grep -c handles_launched_at dev_launch.py # 2+"; the real count
+  # there is 1 (the definition) with the other two occurrences in postbox.py. A count
+  # assertion would have reported FAILED on a byte-perfect install.
+  markers: "postbox.py:warn_if_handle_looks_wrong dev_launch.py:handles_launched_at"
 
 steps:
   - name: Stage the v3.0.0 wheel
     upload:
-      src: /home/lkraven/development/althing/dist/althing_core-3.1.0-py3-none-any.whl
+      src: /home/lkraven/development/althing/dist/althing_core-3.1.1-py3-none-any.whl
       dest: "{{ wheel_dest }}"
       mode: "0644"