feat(engine): T-1131 browse data proxy — six entity kinds, index+detail, one wire envelope (D-254 SS4)

browse_reader.rs: BrowseReader on the CityContextReader::open() pattern
— six index + six detail reads against systems.db (bodies filterable by
containing system; system/corporation/commodity details fold their join
partners). browse_proxy.rs: BrowseRequest{browse, kind, query} /
BrowseResponse{kind, status, index, detail} wire types + dispatcher;
BrowseIndexRow{id, primary, secondary} generic across kinds;
BrowseDetail a per-kind enum of field-exhaustive structs.

Demux: Inbound::BrowseRequest is the FIFTH map shape — deliberately the
last; the doc's four-shape ceiling is re-pinned at five with rationale
(six kinds x two forms folded into ONE envelope whose internal enums
pick sub-behavior, the AtlasLayerRequest.up_to precedent, instead of
twelve top-level shapes) and a hard rule that a sixth shape must
migrate to the D-225 tagged-envelope framing. Served for BOTH roles,
connection-tagged 1:1 in-order like atlas/starmap/citynames.
serve_browse_requests pub so integration tests drive the true
end-to-end pipeline. Wire-only per D-254 (T-949 precedent); v1
exclusions (cascade geometry, event logs) respected.

30 unit tests + 7 bridge_tcp integration tests (six-kind round-trip
over real TCP, reader-can-browse, no crossed responses between two
readers, unknown-id NotFound, empty-table Ready); 2 pre-existing tests
updated for the new receive_bridge_inputs parameter.

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

server/src/bridge/local.rs

@@ -4,6 +4,7 @@
 
 use super::{decode_inbound, BridgeError, Inbound, ObserverSnapshot, SimBridge};
 use crate::atlas::atlas_data_proxy::{CityNamesResponse, StarMapResponse};
+use crate::atlas::browse_proxy::BrowseResponse;
 use crate::atlas::layer_proxy::AtlasLayerResponse;
 use crate::bridge::framing::{read_framed, write_framed};
 use std::fs;
@@ -166,6 +167,16 @@ impl SimBridge for LocalBridge {
         write_framed(writer.get_mut(), &payload)?;
         Ok(())
     }
+
+    fn send_browse_response(&self, resp: &BrowseResponse) -> Result<(), BridgeError> {
+        let payload = rmp_serde::to_vec_named(resp)?;
+        let mut writer = self
+            .writer
+            .lock()
+            .map_err(|e| BridgeError::MutexPoisoned(format!("writer: {}", e)))?;
+        write_framed(writer.get_mut(), &payload)?;
+        Ok(())
+    }
 }
 
 impl Drop for LocalBridge {