feat: add Hermes conservative preset

[cafitac]

Summary

• add a named Hermes hook preset surface with conservative defaults selected by default
• make bootstrap/install/snippet/doctor render conservative hook budgets explicitly, with --preset balanced for the previous verbose shape
• document the safe always-on Hermes defaults and balanced opt-in path

Conservative default contract

• --top-k 1
• --max-prompt-lines 6
• --max-prompt-chars 800
• --max-prompt-tokens 200
• --max-verification-steps 1
• --max-alternatives 0
• --max-guidelines 1
• --no-reason-codes
• timeout: 8

Test plan

• uv run pytest tests/test_cli.py::test_python_module_cli_hermes_bootstrap_defaults_to_user_paths_and_conservative_preset tests/test_cli.py::test_python_module_cli_hermes_hook_config_snippet_can_use_balanced_preset -q
• uv run pytest tests/test_cli.py tests/test_repository_trust_docs.py -q
• uv run pytest tests/ -q
• uv run python scripts/check_release_metadata.py
• uv run python scripts/smoke_release_readiness.py
• npm pack --dry-run
• git diff --check