Release v2.1.0: Opus 4.8-tuned pm-ai-shipping audits + CHANGELOG-driven release automation

pm-ai-shipping: mandatory Evidence citations verified before reporting,
concrete subagent fan-out contract, read-only allowed-tools on both audits,
N+1/waterfall detection and a refute pass in the performance audit,
untrusted-input hardening across the kit, parallel audits in /ship-check,
severity anchors + report consolidation, repo-relative paths.

Repo: CHANGELOG.md as release source of truth with auto-tag-and-release on
merge to main (adapted from phuryn/claude-usage, minus the .vsix build),
Tests workflow on every PR/push, unit + docs-consistency test suite,
contributor-credit conventions in CONTRIBUTING, all manifests synced at 2.1.0.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_011URgT9hYuNrXeCvzjnqRxJ

.claude-plugin/marketplace.json

@@ -1,7 +1,7 @@
 {
   "$schema": "https://anthropic.com/claude-code/marketplace.schema.json",
   "name": "pm-skills",
-  "version": "2.0.0",
+  "version": "2.1.0",
   "description": "Structured AI workflows for better product decisions. 68 domain-specific skills and 42 chained workflows across 9 PM plugins — from discovery to strategy, execution, launch, growth, and shipping AI-built software.",
   "owner": {
     "name": "Paweł Huryn",