fix: simplify purgatory sync - fix SelfSubscriber sync_level upgrade and negentropy fallback

Three targeted fixes for purgatory announcement sync:

1. SelfSubscriber sync_level upgrade: After or_insert_with in process_batch,
   always set entry.sync_level = SyncLevel::Full so that when a promoted
   announcement is broadcast via notify_event and SelfSubscriber receives it,
   an existing StateOnly entry gets upgraded to Full and PR event subscriptions
   are triggered immediately (not delayed up to 24h).

2. Negentropy fallback filter split: In handle_eose, when falling back from
   negentropy to REQ+EOSE, split batch_repos by SyncLevel and call
   build_sync_level_aware_filters instead of build_layer2_and_layer3_filters.
   Prevents StateOnly (purgatory) repos from getting Layer 2 #a/#A/#q filters
   prematurely, which caused nostr-sdk client deduplication to permanently
   drop PR events after orphan rejection.

3. Recompute sync filters after announcement batch EOSE: Add
   recompute_new_sync_filters_for_relay calls at all three batch-completion
   paths in handle_eose for generic filter (announcement) batches. This
   triggers state-only subscriptions for any purgatory repos registered during
   that batch, fixing the 24h delay before state event sync starts.

4. User-submitted purgatory announcements: Add repo_sync_index field to
   PolicyContext with setter/getter, wire in main.rs after SyncManager
   creation, and register in AcceptPurgatory handler so user-submitted
   announcements get StateOnly sync started immediately.

5. Update archive tests: test_archive_without_state_events_does_not_sync_git
   updated to reflect that StateOnly subscription now proactively fetches
   state events from source relays. test_archive_read_only_creates_bare_repo
   un-ignored as it now works end-to-end.

1 files changed, 19 insertions, 0 deletions

diff --git a/src/nostr/policy/mod.rs b/src/nostr/policy/mod.rs
index 1566b6c..c958586 100644
--- a/src/nostr/policy/mod.rs
+++ b/src/nostr/policy/mod.rs
@@ -20,6 +20,7 @@ pub use crate::git::sync::AlignmentResult;
 
 use super::SharedDatabase;
 use crate::purgatory::Purgatory;
+use crate::sync::RepoSyncIndex;
 use nostr_relay_builder::LocalRelay;
 use std::sync::Arc;
 
@@ -34,6 +35,8 @@ pub struct PolicyContext {
     pub local_relay: Arc<std::sync::RwLock<Option<LocalRelay>>>,
     /// Configuration reference for policy settings (includes blacklists)
     pub config: crate::config::Config,
+    /// Repo sync index for registering purgatory announcements (set after SyncManager creation)
+    pub repo_sync_index: Arc<std::sync::RwLock<Option<RepoSyncIndex>>>,
 }
 
 impl PolicyContext {
@@ -51,6 +54,7 @@ impl PolicyContext {
             purgatory,
             local_relay: Arc::new(std::sync::RwLock::new(None)),
             config,
+            repo_sync_index: Arc::new(std::sync::RwLock::new(None)),
         }
     }
 
@@ -68,4 +72,19 @@ impl PolicyContext {
         let guard = self.local_relay.read().unwrap();
         guard.clone()
     }
+
+    /// Set the repo sync index after SyncManager has been created.
+    ///
+    /// This allows purgatory announcements submitted by users to be registered
+    /// in the sync index so state event sync starts promptly.
+    pub fn set_repo_sync_index(&self, index: RepoSyncIndex) {
+        let mut guard = self.repo_sync_index.write().unwrap();
+        *guard = Some(index);
+    }
+
+    /// Get a clone of the repo sync index if it has been set.
+    pub fn get_repo_sync_index(&self) -> Option<RepoSyncIndex> {
+        let guard = self.repo_sync_index.read().unwrap();
+        guard.clone()
+    }
 }