operator pronouns: configurable free-text, threaded into prompts

new NixOS module option services.hive-c0re.operatorPronouns
(free text, default 'she/her', example 'they/them'). hive-c0re
takes it as a CLI flag (--operator-pronouns, lib.escapeShellArg'd
in the systemd unit), stores it on Coordinator, threads it into
the meta flake's mkAgent so each agent's systemd service gets
HIVE_OPERATOR_PRONOUNS set. the harness reads the env at boot
and substitutes {operator_pronouns} into the agent / manager
system prompt alongside {label}. nix string is escaped against
backslash + double-quote so non-ascii / quoted values
round-trip safely. prompt addendum: both agent.md and
manager.md mention the operator's pronouns up front so claude
uses them naturally in third-person reference. propagates on
next ↻ R3BU1LD (meta lock bump, no per-agent approval).

hive-c0re/src/migrate.rs

@@ -62,7 +62,13 @@ pub async fn run(coord: &Arc<Coordinator>) -> Result<()> {
     // Phase 3: meta repo.
     let agents = lifecycle::agents_for_meta_listing().await.unwrap_or_default();
     if let Err(e) =
-        meta::sync_agents(&coord.hyperhive_flake, coord.dashboard_port, &agents).await
+        meta::sync_agents(
+            &coord.hyperhive_flake,
+            coord.dashboard_port,
+            &coord.operator_pronouns,
+            &agents,
+        )
+        .await
     {
         tracing::warn!(error = ?e, "migration: meta sync_agents failed");
     }