remove c0re.operatorPronouns and c0re.contextWindowTokens

Both options are now ignored with a warning (the swarm-peers-removed.nix
shape), so a host that still sets one keeps evaluating.

- operatorPronouns: the agents' system prompt names the pronouns as
  she/her, the value the harness fell back to and the option's default.
  The --operator-pronouns flag, HiveEnv field, meta-flake let binding
  and HIVE_OPERATOR_PRONOUNS env var are gone.
- contextWindowTokens: the per-family defaults (haiku 200000, sonnet
  1000000, opus 1000000) move into hive-agent's harness_state as a
  table; the window the API reports after a turn still wins. The
  --context-window-tokens flag, HiveEnv field and the rendered
  HIVE_CONTEXT_WINDOW_TOKENS_<KEY> env vars are gone.

nix/host-modules/c0re-options-removed.nix

@@ -0,0 +1,46 @@
+# Removal shim for `services.hyperhive.c0re.operatorPronouns` and
+# `services.hyperhive.c0re.contextWindowTokens`.
+#
+# A definition of either is ignored and produces a warning, so a host that
+# still sets one keeps evaluating. The agents' system prompt
+# (hive-agent/prompts/system.md) names the operator's pronouns itself, and
+# the harness (hive-agent/src/harness_state.rs) holds the per-model context
+# windows it uses until a turn reports the model's own.
+#
+# Self-contained and deletable, like ./swarm-peers-removed.nix: one file to
+# remove when the deprecation window closes.
+{ lib, config, ... }:
+let
+  cfg = config.services.hyperhive.c0re;
+in
+{
+  options.services.hyperhive.c0re = {
+    operatorPronouns = lib.mkOption {
+      type = lib.types.nullOr lib.types.str;
+      default = null;
+      visible = false;
+      internal = true;
+      description = "Removed and ignored. `null` is \"not set\".";
+    };
+    contextWindowTokens = lib.mkOption {
+      type = lib.types.nullOr (lib.types.attrsOf lib.types.int);
+      default = null;
+      visible = false;
+      internal = true;
+      description = "Removed and ignored. `null` is \"not set\".";
+    };
+  };
+
+  config.warnings =
+    lib.optional (cfg.operatorPronouns != null) ''
+      services.hyperhive.c0re.operatorPronouns is removed and ignored: the
+      operator's pronouns will be a per-operator profile setting. Until then
+      every agent's system prompt says she/her. Remove this setting.
+    ''
+    ++ lib.optional (cfg.contextWindowTokens != null) ''
+      services.hyperhive.c0re.contextWindowTokens is removed and ignored: the
+      agent harness uses the context window the model reports after each
+      turn, and before the first one its own defaults (haiku 200000, sonnet
+      1000000, opus 1000000 tokens). Remove this setting.
+    '';
+}