replace state.json cache with bincode state.bin

Faster serialization/deserialization, smaller on disk (4.2MB vs 5.9MB).
Automatic migration from state.json on first load — reads the JSON,
writes state.bin, deletes the old file.

Added list-keys, list-edges, dump-json commands so Python scripts no
longer need to parse the cache directly. Updated bulk-categorize.py
and consolidation-loop.py to use the new CLI commands.

src/main.rs

@@ -59,6 +59,9 @@ fn main() {
         "apply-agent"           => cmd_apply_agent(&args[2..]),
         "digest"                => cmd_digest(&args[2..]),
         "trace"                 => cmd_trace(&args[2..]),
+        "list-keys"             => cmd_list_keys(),
+        "list-edges"            => cmd_list_edges(),
+        "dump-json"             => cmd_dump_json(),
         _ => {
             eprintln!("Unknown command: {}", args[1]);
             usage();
@@ -103,7 +106,10 @@ Commands:
   apply-agent [--all]       Import pending agent results into the graph
   digest daily [DATE]       Generate daily episodic digest (default: today)
   digest weekly [DATE]      Generate weekly digest (any date in target week)
-  trace KEY                 Walk temporal links: semantic ↔ episodic ↔ conversation");
+  trace KEY                 Walk temporal links: semantic ↔ episodic ↔ conversation
+  list-keys                 List all node keys (one per line)
+  list-edges                List all edges (tsv: source target strength type)
+  dump-json                 Dump entire store as JSON");
 }
 
 fn cmd_search(args: &[String]) -> Result<(), String> {
@@ -738,6 +744,33 @@ fn cmd_trace(args: &[String]) -> Result<(), String> {
     Ok(())
 }
 
+fn cmd_list_keys() -> Result<(), String> {
+    let store = capnp_store::Store::load()?;
+    let mut keys: Vec<_> = store.nodes.keys().collect();
+    keys.sort();
+    for key in keys {
+        println!("{}", key);
+    }
+    Ok(())
+}
+
+fn cmd_list_edges() -> Result<(), String> {
+    let store = capnp_store::Store::load()?;
+    for rel in &store.relations {
+        println!("{}\t{}\t{:.2}\t{:?}",
+            rel.source_key, rel.target_key, rel.strength, rel.rel_type);
+    }
+    Ok(())
+}
+
+fn cmd_dump_json() -> Result<(), String> {
+    let store = capnp_store::Store::load()?;
+    let json = serde_json::to_string_pretty(&store)
+        .map_err(|e| format!("serialize: {}", e))?;
+    println!("{}", json);
+    Ok(())
+}
+
 fn cmd_interference(args: &[String]) -> Result<(), String> {
     let mut threshold = 0.4f32;
     let mut i = 0;