feat(1001): story_ids filter for recover_half_written_items

The first dry-run against the live pipeline surfaced 735 orphans (35
tombstoned half-writes, 700 stale content rows with no CRDT entry —
mostly artefacts of the pre-numeric-id era). Bulk-recovering would
resurrect a lot of stories the user deliberately purged in the past.

Add an optional `story_ids` filter that restricts both discovery (in
dry-run) and recovery to a named subset, so the operator can target
the specific recent half-writes without touching anything else. The
new test asserts the filter is honoured.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

server/src/db/recover.rs

@@ -84,13 +84,23 @@ pub fn find_half_written_items() -> Vec<HalfWritten> {
 ///    the orphan is left in place.
 /// 5. Deletes the orphan's content-store + shadow-DB rows via `delete_item`.
 ///
+/// If `only` is provided, recovery operates only on orphans whose `story_id`
+/// is in the list — everything else is left alone.  This is the safe default
+/// for a live system that may have many historic purged ids visible as
+/// orphans alongside the genuinely-recent half-writes.
+///
 /// Returns a (`old_id`, `new_id`, `name`) mapping for every successful
 /// recovery.  Orphans that failed to recover are simply omitted from the
 /// returned list and logged at WARN level.
-pub fn recover_half_written_items() -> Vec<RecoveryResult> {
+pub fn recover_half_written_items(only: Option<&[String]>) -> Vec<RecoveryResult> {
     let orphans = find_half_written_items();
     let mut results = Vec::with_capacity(orphans.len());
     for orphan in orphans {
+        if let Some(filter) = only
+            && !filter.iter().any(|f| f == &orphan.story_id)
+        {
+            continue;
+        }
         match recover_one(&orphan) {
             Ok(result) => results.push(result),
             Err(e) => {
@@ -358,7 +368,7 @@ mod tests {
         assert_eq!(entry.name, "Tombstoned Then Half-Written");
 
         // Run the recovery and inspect the mapping.
-        let results = recover_half_written_items();
+        let results = recover_half_written_items(None);
         let mapping = results
             .iter()
             .find(|r| r.old_id == old_id)
@@ -382,10 +392,44 @@ mod tests {
         );
 
         // Re-running recovery is a no-op (no orphans left).
-        let again = recover_half_written_items();
+        let again = recover_half_written_items(None);
         assert!(
             again.iter().all(|r| r.old_id != old_id),
             "recovery should be idempotent for the same orphan"
         );
     }
+
+    /// The `only` filter restricts recovery to a specific id set; orphans
+    /// outside the filter are left alone.
+    #[test]
+    fn recover_only_filter_restricts_recovery_to_named_ids() {
+        crdt_state::init_for_test();
+        crate::db::ensure_content_store();
+
+        // Two orphans, only one in the filter.
+        let recover_id = "9810";
+        let keep_id = "9811";
+        for id in [recover_id, keep_id] {
+            let name = format!("Item {id}");
+            let content = body(&name, "refactor", None);
+            write_item_with_content(id, "1_backlog", &content, ItemMeta::named(&name));
+            crdt_state::evict_item(id).expect("evict should succeed");
+            crate::db::content_store::write_content(ContentKey::Story(id), &content);
+        }
+
+        let results = recover_half_written_items(Some(&[recover_id.to_string()]));
+        assert_eq!(results.len(), 1, "exactly one orphan should be recovered");
+        assert_eq!(results[0].old_id, recover_id);
+
+        // The filtered-out orphan must still be a half-written item.
+        let half = find_half_written_items();
+        assert!(
+            half.iter().any(|h| h.story_id == keep_id),
+            "filtered-out orphan should remain"
+        );
+        assert!(
+            half.iter().all(|h| h.story_id != recover_id),
+            "recovered orphan should be gone"
+        );
+    }
 }