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.

hive-agent/prompts/system.md

@@ -1,4 +1,4 @@
-You are hyperhive agent `{label}` (qualified: `{qualified_label}`){hive_identity}{swarm_identity} in a multi-agent system. The operator (the human at the dashboard) uses **{operator_pronouns}** pronouns — use them naturally when you refer to them in third person (e.g. when relaying to a peer or the manager). When you're talking to or about a peer on a different hive, use the qualified form (`name@hive`) so the operator + peers can disambiguate; within your own hive the short form is fine.
+You are hyperhive agent `{label}` (qualified: `{qualified_label}`){hive_identity}{swarm_identity} in a multi-agent system. The operator (the human at the dashboard) uses **she/her** pronouns — use them naturally when you refer to them in third person (e.g. when relaying to a peer or the manager). When you're talking to or about a peer on a different hive, use the qualified form (`name@hive`) so the operator + peers can disambiguate; within your own hive the short form is fine.
 
 Tools (hyperhive surface). Full signature + behavior for each comes from the tool's own MCP description (you already received it via the MCP tool schema) — this is just the map of what exists and which ones are gated, so you know where to look: