v0.2.0

0.2.0 — First release with an external contribution

MINOR: new features and adapters; compiled output for existing policies is unchanged
(golden-suite verified), but new surfaces exist.

• Antigravity CLI adapter — contributed by @alexsmolya, the project's first external
  contribution: .agents/rules/chock.md workspace rule, ambient/git-hook/CI surfaces
  (deliberately not pre-tool-use: no installer exists, so no claim is made).
• Claude-format plugin emitter: chock plugin build --format claude|all --out-dir
  renders each policy into Claude Code's plugin layout (read natively by Claude Code,
  Copilot CLI, VS Code and Grok Build), with the fail posture stated verbatim in every
  emitted description and per-format subtrees so no package has to lie for another
  client. Stale-output reconciliation, duplicate-id refusal.
• chock marketplace build: derives the marketplace index, a content-addressed
  chock-market.lock (sha256 per published plugin directory), and a generated
  PLUGINS.md catalog page from the built packages — never hand-listed, drift-checked.
• Hook interpreter honesty: the emitted hook command stays a single python3
  invocation -- a review of the proposed python3 || python fallback proved a chain
  can erase a deny verdict (a deny exit followed by a missing-interpreter exit reads
  as an error, and the first leg consumes stdin), so it was rejected with
  measurements. Instead every emitted description now states the per-client fail
  posture: fail-open clients allow silently without python3 and a usable bash;
  fail-closed clients (VS Code) refuse matched commands; Windows needs the
  Microsoft Store python3 alias disabled or Python installed.
• Supply chain: the Marketplace action no longer interpolates workflow inputs
  into shell (two HIGH template-injection alerts, fixed by env indirection); GitHub
  Releases are created by the runner's own gh CLI instead of a third-party action;
  the semgrep scanner installs hash-pinned via compiled requirements; Dependabot
  gets a 7-day cooldown.
• CI pressure testing: zizmor, actionlint, ShellCheck, and Semgrep (with custom
  rules encoding this project's own incidents) run as required checks; all three
  public repos are at zero open code-scanning alerts.
• Fix: chock remove refuses when a policy's manifest cannot be read — an
  unreadable manifest previously read as "not mandatory" and allowed deletion.
• Fix: frontier_ingest no longer prints and exits at import time; frontier
  validation shares one STANDARDS_DIR with ingestion.
• Tests: 755 (from 736); statement coverage 83%; new suites for the plugin
  emitter, marketplace, chock remove, and the frontier validation modes.