fix(simulation): PR #176 review round — all 12 findings + 2 recommendations addressed

H1 demux: ShapeProbe defensive multi-shape rejection (union frames now Err, not first-match; +2 tests) and doc claim made honest. H2/T1 SystemIndex.reset_test_state() folded into SimBridge.reset_test_state() (load() inline per autoload rule) + has_pending_request() accessor. H3 no-op tests now assert the replay flag both directions. H4 retry test actually ingests a failure and asserts the retry semantic. H5 error fixture uses the normalized status string. H6 bridge_tcp e2e sends all five frame shapes over real TCP (star-map + city-names buffers asserted). H7 positive replay-on-CONNECTED test via the test_local_bridge test-mode-flip precedent (stub bridge captures + decodes the request bytes). H8/T2 stale PLACEHOLDER doc replaced with the confirmed contract. H9 is_capital doc matches the COALESCE reality. T-r1 demux ceiling written down (next shape = tagged envelope). T-r2 AtlasLayerResponse governance ceiling comment. Lead item: the four cargo-fmt-formatted files from the gate round are now committed (layer_proxy/plugin/bridge-mod/main). H10 note for the record: the 13 snapshot_*.msgpack fixtures in commit 845737617 were regenerated because they were stale against their own generator (pre-existing version-key removal) — verified harmless, no client reads that key.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

server/src/atlas/plugin.rs

@@ -863,10 +863,8 @@ mod tests {
         use std::sync::atomic::{AtomicU32, Ordering};
         static SEQ: AtomicU32 = AtomicU32::new(0);
         let n = SEQ.fetch_add(1, Ordering::Relaxed);
-        let path = std::env::temp_dir().join(format!(
-            "sr_plugin_starmap_{}_{n}.json",
-            std::process::id()
-        ));
+        let path =
+            std::env::temp_dir().join(format!("sr_plugin_starmap_{}_{n}.json", std::process::id()));
         std::fs::write(&path, r#"{"_meta": {}, "nodes": [], "edges": []}"#).unwrap();
 
         let mut world = World::new();