Run SDK evolution across all vendor packages

[ebarti]

Summary

Runs the local SDK evolution workflow across the full default vendor package set instead of only google-antigravity.

This PR supersedes the narrower Antigravity-only proof by carrying forward the candidate API diff hardening and adding an all-package report/lock update.

Documentation Added

Adds docs/sdk-evolution-agent-design.md before implementing changelog and behavior-probe changes. The design document defines:

• report-only, real-runtime, all-package, implementation, and draft-PR operating modes,
• primary changelog and release-note sources for Claude, Codex, Codex CLI, and Antigravity,
• why API signatures are necessary but not sufficient,
• behavior probe tiers for unit, installed-SDK contract, and optional live checks,
• deterministic gates for missing diffs, missing release-note evidence, failed behavior probes, reviewer rejection, and recursive self-adaptation,
• visuals for the full workflow, runtime analysis sequence, behavior probes, and self-adaptation,
• caveats, concerns, and alternatives considered.

docs/sdk-evolution-agent.md now links to this design doc from the user-facing run guide.

Agent-Generated Evidence

The committed report was generated through agent-runtime-kit using the real antigravity-agent-sdk runtime from a temporary pre-update checkout, with no --package filter:

env -u UV_EXCLUDE_NEWER uv run python -m examples.sdk_evolution_agent \
  --runtime antigravity-agent-sdk \
  --refresh-preview \
  --report-dir /tmp/ark-sdk-evolution-all-report

Committed report:

reports/sdk-evolution-all-packages/20260622T091555Z/report.md

The resolver found two update candidates:

• claude-agent-sdk: 0.2.96 -> 0.2.106
• google-antigravity: 0.1.2 -> 0.1.4

Codex package status:

• openai-codex: already current at 0.1.0b3
• openai-codex-cli-bin: no resolver update; the lock remains on 0.137.0a4, which is newer than PyPI's stable latest metadata field

Implementation

• Updates uv.lock for claude-agent-sdk to 0.2.106.
• Keeps the Antigravity lock update to google-antigravity 0.1.4.
• Replaces the Google-only proof artifact with an all-package proof artifact.
• Uses resolver update targets from uv lock --dry-run -P ... for candidate API snapshots, avoiding false downgrade diffs when PyPI stable latest is lower than a locked prerelease.
• Adds regression coverage for resolver-target candidate snapshotting.

Verification

• env -u UV_EXCLUDE_NEWER uv run ruff check .
• env -u UV_EXCLUDE_NEWER uv run mypy
• env -u UV_EXCLUDE_NEWER uv run pytest (99 passed, 3 skipped)
• env -u UV_EXCLUDE_NEWER uv lock --check
• env -u UV_EXCLUDE_NEWER uv lock --dry-run -P claude-agent-sdk -P openai-codex -P openai-codex-cli-bin -P google-antigravity (No lockfile changes detected)
• env -u UV_EXCLUDE_NEWER AGENT_RUNTIME_KIT_LIVE=1 AGENT_RUNTIME_KIT_LIVE_PROVIDER=all uv run pytest tests/test_live_smoke.py -q -s (3 passed)

Antigravity Comparison With PR #8

Compared with PR #8 (sdk-evolution-proof-20260622):

• src/agent_runtime_kit/adapters/antigravity.py: no diff.
• tests/test_antigravity_adapter.py: no diff.
• google-antigravity lock state: unchanged at 0.1.4.
• google-antigravity API diff artifact: identical to PR Update google-antigravity from SDK evolution report #8.
• Difference is scope: this PR replaces the Google-only report with an all-package report and adds the Claude lock update plus resolver-target candidate selection.

Safety

• No auto-merge.
• No unsupported credential scraping.
• Freshness cutoffs are explicitly removed for SDK evolution commands.
• Candidate SDK inspection uses temporary isolated virtualenvs.

Codex Model Policy

Codex-backed SDK evolution stages now explicitly run with model=gpt-5.5 and reasoning_effort=xhigh. The override is scoped to codex-agent-sdk only; Claude and Antigravity keep provider-native model selection because gpt-5.5 is not a portable model id across adapters.

[ebarti]

Superseded by the split PRs: #10 contains the SDK evolution example/tooling fixes; #11 contains only the generated SDK update run artifacts and lockfile changes, stacked on #10.