Prepare v0.2.2 patch release

[alejandro-ao]

Summary

• Bump package/runtime versions and lockfile to 0.2.2.
• Document changes since v0.2.1 and update the pinned install example.
• Note Pi agent_settled and Telegram draft compatibility requirements.

Verification

• uv run --locked ruff check .
• uv run --locked mypy pi_gateway tests
• uv run --locked pytest -q (47 passed, 20 subtests passed)
• python3 -m compileall -q pi_gateway main.py
• uv build
• uv run --locked pi-gateway --version
• git diff --check

[Copilot]

Copilot review overview

🟢 Approval recommended

Version references are consistent and the release notes accurately reflect the implemented behavior.

Review effort: Balanced
Findings: None

What changed in this PR

Prepares the consistent v0.2.2 release across package metadata, documentation, and lockfile.

Changes:

• Bumps runtime/package versions to 0.2.2.
• Updates the pinned installation example.
• Documents new instance management, Pi RPC, model picker, and Telegram draft behavior.

File	Description
uv.lock	Updates the locked project version.
README.md	Pins installation to v0.2.2.
pyproject.toml	Bumps package metadata.
pi_gateway/​__init__.py	Bumps the runtime version constant.
CHANGELOG.md	Adds v0.2.2 release notes and compatibility requirements.

---

💡 Add a code-review agent skill or configure MCP servers for context-aware, tailored reviews. Learn more in the docs.