0.31.0

Added

• ess-entity-runtime projects an admitted service contract into validated Entity Runtime
  definitions and typed host binding obligations. It preserves conditional outcome selection,
  exact values and event order, and makes omitted operation-field actions explicit without
  executing a service or choosing the host's policy.
  Subject-field, state-change and external conditions lower to ER predicates; an operation
  that clears a field and a preserve that returns no response are refused by name
  (ClearedValueUnsupported, SilentPreserveUnsupported).
  A lowering targets Entity Runtime 0.23.0: ENTITY_RUNTIME_REVISION is the locked
  entity-core commit, and a test refuses a lock file that names another.
• ess-service-contract extracts a borrowed service contract for an exact component and
  synthesis plan, preserving selected compiler values, contextual capabilities, obligations,
  refusals and their original order.
• A release note for 0.28–0.30 (website/blog/2026-09-25-1200-what-a-retry-returns.md): subject
  history in ess/6, retried results in ess/7, and the plugin's one release here. Without it the
  newest note trails 0.31.0 by four minors and cargo xtask docs refuses the tree.

Removed

• Breaking: ess skill and the agent plugin in plugins/ess/, with both marketplace files
  (ess@ess), the build.rs that embedded the skills and cargo xtask plugin check. The plugin
  lives in beyond10x/agentplugins with every other Beyond10x plugin (ess@b10x, skills
  ess:init, ess:specifying, ess:retrofitting, ess:testing-conformance, ess:upgrade);
  its b10x CLI installs this binary prebuilt or with cargo and migrates an ess@ess install.
  ess --help lists the four areas and nothing else.