docs: clarify why fetch_repository_data excludes purgatory

Add comments explaining that PR event processing (both incoming and
purgatory) should only use database announcements, not purgatory ones.

This is intentional because:
- Incoming PR events should only be accepted for validated announcements
- Purgatory PR events should only be released when announcement is promoted
- This prevents accepting PR events for announcements that fail validation

Differs from state event processing which uses fetch_repository_data_with_purgatory
because state events check authorization without releasing from purgatory.

2 files changed, 11 insertions, 0 deletions

diff --git a/src/git/sync.rs b/src/git/sync.rs
index a0b7c47..4b35023 100644
--- a/src/git/sync.rs
+++ b/src/git/sync.rs
@@ -1171,6 +1171,9 @@ async fn process_purgatory_pr_events(
     );
 
     // Fetch repository data for syncing
+    // NOTE: Only fetch from database, NOT purgatory. PR events should only be
+    // released from purgatory when the announcement has been promoted (validated).
+    // This ensures we don't accept PR events for announcements that fail validation.
     let db_repo_data = match fetch_repository_data(database, identifier).await {
         Ok(data) => data,
         Err(e) => {
diff --git a/src/nostr/policy/pr_event.rs b/src/nostr/policy/pr_event.rs
index 00e09c3..072e445 100644
--- a/src/nostr/policy/pr_event.rs
+++ b/src/nostr/policy/pr_event.rs
@@ -127,6 +127,10 @@ impl PrEventPolicy {
                 .ok_or_else(|| anyhow::anyhow!("No identifier in PR event"))?;
 
             // Fetch repository data
+            // NOTE: Only fetch from database, NOT purgatory. Incoming PR events should
+            // only be accepted for announcements that have been promoted (validated).
+            // If the announcement is still in purgatory, the PR event should also go
+            // to purgatory and wait for the announcement to be promoted.
             let db_repo_data = fetch_repository_data(&self.ctx.database, &identifier).await?;
 
             // Extract owner pubkey from source repo path
@@ -203,6 +207,10 @@ impl PrEventPolicy {
         let identifier = parts[2];
 
         // 2. Fetch repo data
+        // NOTE: Only fetch from database, NOT purgatory. Incoming PR events should
+        // only be accepted for announcements that have been promoted (validated).
+        // If the announcement is still in purgatory, the PR event should also go
+        // to purgatory and wait for the announcement to be promoted.
         let db_repo_data = fetch_repository_data(&self.ctx.database, identifier).await?;
 
         // 3. Extract list of maintainers from "a 30617:<maintainer>:<identifier>" tags