fix(pr-reengagement): evict no-PR completed issues to stop log flood

state.completed only ever shed an issue when PrReengagement dispatched a
re-engagement, so any completed issue that never re-engages sat in the set
until orchestrator restart. PrReengagement re-scans the whole set every
poll cycle, emitting skip_no_pr / skip_no_critical per lingering issue —
~2880 events/day each, the dominant source of decision-log flood.

A completed issue with no PR url can never produce a review to re-engage
on, so this evicts it from state.completed on the no-PR branch instead of
re-scanning it forever. If it is later re-dispatched and opens a PR, the
normal completion path re-adds it.

Scoped to the no-PR case only. The skip_no_critical path (PR present, no
critical review yet) is left intact because a review can still arrive
minutes after the agent exits — the exact late-review window
PrReengagement exists to catch (SYM-16).

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

Author: viniciuscffreitas

elixir/lib/symphony_elixir/orchestrator/pr_reengagement.ex

@@ -98,7 +98,13 @@ defmodule SymphonyElixir.Orchestrator.PrReengagement do
           identifier: issue.identifier
         })
 
-        state
+        # A completed issue with no PR can never produce a review to
+        # re-engage on, so evict it from `state.completed` instead of
+        # re-scanning it every poll cycle — the dominant source of the
+        # decision-log flood (skip_no_pr fired ~2880x/day per lingering
+        # issue). If it is later re-dispatched and opens a PR, the normal
+        # completion path re-adds it. Safe: no PR means nothing to lose.
+        %{state | completed: MapSet.delete(state.completed, issue.id)}
 
       pr_url ->
         detector_fn = Map.fetch!(opts, :detector_fn)

elixir/test/symphony_elixir/orchestrator/pr_reengagement_test.exs

@@ -355,7 +355,7 @@ defmodule SymphonyElixir.Orchestrator.PrReengagementTest do
       refute_receive :commented, 50
     end
 
-    test "no-op when fetched issue has no PR url (defensive)" do
+    test "evicts a completed issue that has no PR url" do
       parent = self()
 
       issue_no_pr = %Issue{
@@ -385,8 +385,11 @@ defmodule SymphonyElixir.Orchestrator.PrReengagementTest do
           end
         })
 
-      assert ^state = PrReengagement.run(state, opts)
+      new_state = PrReengagement.run(state, opts)
 
+      # No PR means nothing to re-engage on, so the issue is dropped from
+      # state.completed and will not be re-scanned every poll cycle.
+      refute MapSet.member?(new_state.completed, "i-no-pr")
       refute_receive :detector_called, 50
       refute_receive :transitioned, 50
       refute_receive :commented, 50
@@ -422,7 +425,7 @@ defmodule SymphonyElixir.Orchestrator.PrReengagementTest do
       refute_receive :commented, 50
     end
 
-    test "no-op when fetched issue carries repos but none have a PR yet (defensive flat_map fallback)" do
+    test "evicts a completed issue whose repos carry no PR yet (defensive flat_map fallback)" do
       parent = self()
 
       issue_repo_no_pr = %Issue{
@@ -451,8 +454,9 @@ defmodule SymphonyElixir.Orchestrator.PrReengagementTest do
           end
         })
 
-      assert ^state = PrReengagement.run(state, opts)
+      new_state = PrReengagement.run(state, opts)
 
+      refute MapSet.member?(new_state.completed, "i-pre-pr")
       refute_receive :detector_called, 50
       refute_receive :transitioned, 50
       refute_receive :commented, 50