matrix-accounts dashboard: live status + homeserver from daemon snapshot (be-4)

hive-matrix-mcp/src/paths.rs

@@ -58,6 +58,21 @@ pub fn matrix_state_dir() -> PathBuf {
     PathBuf::from(format!("{state_dir}/matrix-sdk-state"))
 }
 
+/// Resolve the live-accounts snapshot file the daemon writes after
+/// startup restores. Override via `HIVE_MATRIX_ACCOUNTS_FILE`; default
+/// is `<HYPERHIVE_STATE_DIR>/matrix-accounts.json` — the host-visible
+/// per-agent state dir (sibling to `matrix-token`) that hive-c0re's
+/// dashboard reads to backfill live up/down status + the effective
+/// homeserver for each provisioned account.
+#[must_use]
+pub fn accounts_file() -> PathBuf {
+    if let Some(p) = std::env::var_os("HIVE_MATRIX_ACCOUNTS_FILE") {
+        return PathBuf::from(p);
+    }
+    let state_dir = std::env::var("HYPERHIVE_STATE_DIR").unwrap_or_default();
+    PathBuf::from(format!("{state_dir}/matrix-accounts.json"))
+}
+
 /// Hyperhive control socket — the daemon writes wake signals here so
 /// the harness drives a new claude turn on incoming matrix events.
 /// Mirrors the path `forge_notify` writes to.