huskies: merge 913

server/src/agents/lifecycle.rs

@@ -12,8 +12,8 @@ use std::process::Command;
 
 use crate::db::yaml_legacy::clear_front_matter_field_in_content;
 use crate::pipeline_state::{
-    ApplyError, ArchiveReason, BranchName, GitSha, PipelineEvent, Stage, apply_transition,
-    stage_label,
+    ApplyError, ArchiveReason, BranchName, GitSha, PipelineEvent, Stage, TransitionFired,
+    apply_transition, stage_label,
 };
 use crate::slog;
 
@@ -248,13 +248,22 @@ pub fn transition_to_blocked(story_id: &str, reason: &str) -> Result<(), String>
     .map_err(|e| e.to_string())
 }
 
-/// Transition a story from `Stage::Merge` to `Stage::MergeFailure` via the state machine.
+/// Transition a story from `Stage::Merge` (or `Stage::MergeFailure`) to
+/// `Stage::MergeFailure` via the state machine.
 ///
 /// Builds a `PipelineEvent::MergeFailed { reason }`, validates the transition, writes
 /// the resulting `Stage::MergeFailure` to the CRDT, and persists the reason to front
 /// matter so it survives server restarts.
+///
+/// When the story is already in `MergeFailure`, this is a silent self-loop: the
+/// returned `TransitionFired::before` will be `Stage::MergeFailure`.  Callers
+/// should suppress re-notification in that case to avoid duplicate chat messages.
+///
 /// Returns `Err` on `TransitionError` — callers must NOT fall back to direct register writes.
-pub fn transition_to_merge_failure(story_id: &str, reason: &str) -> Result<(), String> {
+pub fn transition_to_merge_failure(
+    story_id: &str,
+    reason: &str,
+) -> Result<TransitionFired, String> {
     let reason_owned = reason.to_string();
     let transform: Box<dyn Fn(&str) -> String> = Box::new(move |content: &str| {
         crate::db::yaml_legacy::write_merge_failure_in_content(content, &reason_owned)
@@ -266,7 +275,6 @@ pub fn transition_to_merge_failure(story_id: &str, reason: &str) -> Result<(), S
         },
         Some(&*transform),
     )
-    .map(|_| ())
     .map_err(|e| e.to_string())
 }