merge main and port deactivate_stale_deployments + add mise

- Merge main to include PR #131 (deactivate stale deployments)
- Port deactivate_stale_deployments from bash/curl to Octokit in the
  actions/github-script step
- Add mise.toml with bats-core and shellcheck for local dev setup
- Update CI workflow to use jdx/mise-action

Co-Authored-By: Claude <claude@anthropic.com>

Author: 0x46616c6b

action.yml

@@ -231,9 +231,39 @@ runs:
               })
           )];
 
+          // Deactivate stale in-progress/queued/pending deployments for an environment
+          async function deactivateStaleDeployments(environment) {
+            const { data: deployments } = await github.rest.repos.listDeployments({
+              ...context.repo,
+              environment,
+              per_page: 30
+            });
+
+            for (const dep of deployments) {
+              const { data: statuses } = await github.rest.repos.listDeploymentStatuses({
+                ...context.repo,
+                deployment_id: dep.id,
+                per_page: 1
+              });
+
+              const latestState = statuses[0]?.state;
+              if (['in_progress', 'queued', 'pending'].includes(latestState)) {
+                core.info(`Marking stale deployment ${dep.id} (${latestState}) as inactive`);
+                await github.rest.repos.createDeploymentStatus({
+                  ...context.repo,
+                  deployment_id: dep.id,
+                  state: 'inactive',
+                  description: 'Superseded by newer deployment'
+                });
+              }
+            }
+          }
+
           const ids = {};
           for (const env of environments) {
             try {
+              await deactivateStaleDeployments(env);
+
               const { data: deployment } = await github.rest.repos.createDeployment({
                 ...context.repo,
                 ref: context.sha,

mise.toml

@@ -0,0 +1,27 @@
+[tools]
+bats-core = "1.11.0"
+shellcheck = "0.10.0"
+
+[tasks.test]
+description = "Run bats test suite"
+run = """
+#!/usr/bin/env bash
+set -euo pipefail
+
+if [[ ! -d tests/test_helper/bats-support ]]; then
+  git clone --depth 1 https://github.com/bats-core/bats-support.git tests/test_helper/bats-support
+fi
+if [[ ! -d tests/test_helper/bats-assert ]]; then
+  git clone --depth 1 https://github.com/bats-core/bats-assert.git tests/test_helper/bats-assert
+fi
+
+bats tests/*.bats
+"""
+
+[tasks.lint]
+description = "Run shellcheck on all scripts"
+run = "shellcheck --severity=warning scripts/*.sh scripts/lib/*.sh"
+
+[tasks.check]
+description = "Run all checks (lint + test)"
+depends = ["lint", "test"]