chore(release): 0.2.0

[datj9]

Release 0.2.0.

Notable changes

Added

• --write / --plan delegation permission modes: advisor-agnostic intents that crossagent expands into each advisor's concrete permission flags. --plan pins the executor to a read-only planning mode; --write grants unattended edit + command execution (warns when scope is unbounded — steer with --allow-path). The mode carries through --escalate-to rungs and is refused on a read-only executor, so a --write delegation never silently degrades to read-only.
• low reasoning effort for default GPT-6 Astra asks: default gpt-6-astra second opinions now run at low reasoning effort via a visible -c model_reasoning_effort=low override (never modifies ~/.codex/config.toml). Override with --reasoning or advisors.json.
• Per-advisor default_model + model aliases: codex second opinions default to gpt-6-astra, with gpt6/astra aliases scoped to the codex advisor. Override via advisors.json or --model default.

Changed

• --write fails closed outside a git repository: --write now refuses to run (exit 2) when the cwd is not a git worktree, because the delegate's writes can't be scoped or audited against a baseline there. Run from inside a git repo (or point --cwd at one), or drop --write.

Verification

• PYTHONPATH=src python3 -c 'import crossagent; print(crossagent.__version__)' → 0.2.0
• uv run pytest -q → 624 passed

Release steps

After merge: tag v0.2.0 on main and push it to trigger the PyPI publish via release.yml.