hive-agent: a failed turn-end /compact keeps the turn's own compacted flag

The turn-end path returned the /compact's success as the turn's outcome, so a
turn that had already compacted (reactively or per policy) was recorded as not
compacted when its queued /compact then failed. The outcome now folds the two
with `||`, via `with_turn_end_compact`, which the tests pin.

hive-agent/src/turn.rs

@@ -461,7 +461,7 @@ pub async fn drive_turn(
         // Reflect `Compacting` in the UI like the idle path (`run_pending_compact`)
         // does; the serve loop resets to `Idle` once this turn returns.
         bus.set_state(crate::events::TurnState::Compacting);
-        let compacted = report_compact(bus, session.compact(&config, &sink).await);
+        let compact_ok = report_compact(bus, session.compact(&config, &sink).await);
         // If the compact call asked to be woken (the agent's own `compact`
         // tool with a `wake_prompt`), stash it — the serve loop reads it
         // back after this turn returns and drives a synthetic follow-up
@@ -470,7 +470,7 @@ pub async fn drive_turn(
         if let Some(prompt) = request.wake_prompt {
             bus.set_post_compact_wake(prompt);
         }
-        return Ok(compacted);
+        return with_turn_end_compact(outcome, compact_ok);
     }
     outcome
 }
@@ -495,6 +495,13 @@ fn report_compact<E: std::fmt::Display>(bus: &Bus, result: Result<(), E>) -> boo
     }
 }
 
+/// Fold a turn-end `/compact` into the turn's own outcome. A compaction that
+/// ran during the turn (`Ok(true)`) stays recorded even when the turn-end
+/// `/compact` failed; a failed `/compact` never turns it into `Ok(false)`.
+fn with_turn_end_compact(outcome: TurnOutcome, compact_ok: bool) -> TurnOutcome {
+    outcome.map(|turn_compacted| turn_compacted || compact_ok)
+}
+
 /// Pre-turn auto-reset check. If context is large AND the prompt cache has
 /// gone cold (idle time >= cache TTL), archive the current session so the
 /// next wake-up turn's `--resume <title>` misses and self-heals into a fresh
@@ -835,7 +842,7 @@ fn archive_session(bus: &Bus, session: &AgentSession) {
 mod tests {
     use super::{
         PermissionAsk, TurnError, acp_permits, nonzero_or, parse_u64, report_compact,
-        runtime_error_to_turn,
+        runtime_error_to_turn, with_turn_end_compact,
     };
     use crate::events::{Bus, LiveEvent};
     use hive_runtime::{AcpError, Error};
@@ -1001,4 +1008,20 @@ mod tests {
         assert!(compacted);
         assert_eq!(notes, ["/compact done"]);
     }
+
+    #[test]
+    fn a_failed_turn_end_compact_keeps_the_turns_own_compaction() {
+        assert!(matches!(with_turn_end_compact(Ok(true), false), Ok(true)));
+    }
+
+    #[test]
+    fn a_failed_turn_end_compact_leaves_a_plain_turn_uncompacted() {
+        assert!(matches!(with_turn_end_compact(Ok(false), false), Ok(false)));
+    }
+
+    #[test]
+    fn a_successful_turn_end_compact_marks_the_turn_compacted() {
+        assert!(matches!(with_turn_end_compact(Ok(false), true), Ok(true)));
+        assert!(matches!(with_turn_end_compact(Ok(true), true), Ok(true)));
+    }
 }