Code Farm: per-plot auto-replant pause and crop-lock check; community sync and node work

Continuous Delivery could never be turned off once a crop was planted. Add a
one-shot per-plot "stop after harvest" flag (POST /game/plot/stop, Devii tool
game_plot_stop, game_plots.stop_after_harvest), cleared by the next plant,
autoreplant claim or Refactor. Autoreplant now also respects crop locks through
the shared _crop_lock predicate. Plan and measurements in happyplanting.md.

Also includes the pending community sync, node network and related work in the
tree; the full suite passed (4999) with all of it.

Co-Authored-By: Claude Sonnet 5.5 <noreply@anthropic.com>

tests/api/sync/posts.py

@@ -9,11 +9,13 @@ def seed_author(client, admin, origin, uid="u1"):
     return body["results"][0]["local_uid"]
 
 
-def test_unknown_author_is_rejected_with_reason(client, admin, origin):
+def test_unknown_author_is_deferred_with_the_reason_and_what_it_waits_for(client, admin, origin):
     body = sync_ok(client, admin, "posts", origin, [post_record(author="missing")])
     result = body["results"][0]
-    assert result["status"] == "rejected" and result["reason"] == "unknown_author"
+    assert result["status"] == "deferred" and result["reason"] == "unknown_author"
+    assert (result["needs_kind"], result["needs_uid"]) == ("users", "missing")
     assert get_table("sync_links").count(origin=origin) == 0
+    assert get_table("sync_pending").count(origin=origin) == 1
 
 
 def test_create_normalizes_and_has_no_side_effects(client, admin, origin):