left4me: make chown_src self-healing too

Same problem as pip_install: chown_src was triggered:True and only
fired when git_deploy did. After a partial first-apply where git_deploy
succeeded (extracting root-owned files) but the chown didn't happen
yet, subsequent applies left files root-owned forever — pip_install
fails with "permission denied" trying to write .egg-info/.

Drop triggered:True. Add an unless guard:
  test -z "$(find /opt/left4me/src ! -user left4me -print -quit)"
i.e. skip the chown only when no non-left4me-owned file exists in the
tree.

bundles/left4me/items.py

@@ -144,8 +144,11 @@ git_deploy = {
 }
 
 actions['left4me_chown_src'] = {
+    # Runs every apply (cheap — chown -R on a small tree). Self-heals
+    # whenever git_deploy extracts a new tarball as root-owned files.
+    # Not in any triggers list so doesn't need triggered:True.
     'command': 'chown -R left4me:left4me /opt/left4me/src',
-    'triggered': True,
+    'unless': 'test -z "$(find /opt/left4me/src \\! -user left4me -print -quit 2>/dev/null)"',
     'cascade_skip': False,
     'needs': [
         'git_deploy:/opt/left4me/src',