remove hardcoded skip lists, prune orphan edges in fsck

All nodes in the store are memory — none should be excluded from
knowledge extraction, search, or graph algorithms by name. Removed
the MEMORY/where-am-i/work-queue/work-state skip lists entirely.
Deleted where-am-i and work-queue nodes from the store (ephemeral
scratchpads that don't belong). Added orphan edge pruning to fsck
so broken links get cleaned up automatically.

Co-Authored-By: ProofOfConcept <poc@bcachefs.org>

src/main.rs

@@ -416,18 +416,31 @@ fn cmd_fsck() -> Result<(), String> {
     store::fsck()?;
     store::strip_md_keys()?;
 
-    // Check for broken links
-    let store = store::Store::load()?;
-    let mut orphans = 0usize;
+    // Prune broken links (relations referencing deleted/missing nodes)
+    let mut store = store::Store::load()?;
+    let mut to_tombstone = Vec::new();
     for rel in &store.relations {
         if rel.deleted { continue; }
         if !store.nodes.contains_key(&rel.source_key)
             || !store.nodes.contains_key(&rel.target_key) {
-            orphans += 1;
+            let mut tombstone = rel.clone();
+            tombstone.deleted = true;
+            tombstone.version += 1;
+            to_tombstone.push(tombstone);
         }
     }
-    if orphans > 0 {
-        eprintln!("{} broken links (run `health` for details)", orphans);
+    if !to_tombstone.is_empty() {
+        let count = to_tombstone.len();
+        store.append_relations(&to_tombstone)?;
+        for t in &to_tombstone {
+            if let Some(r) = store.relations.iter_mut().find(|r|
+                r.source == t.source && r.target == t.target && !r.deleted) {
+                r.deleted = true;
+                r.version = t.version;
+            }
+        }
+        store.save()?;
+        eprintln!("Pruned {} broken links", count);
     } else {
         eprintln!("No broken links");
     }