Release 0.2.0: changelog, version reporting, push-to-deploy

- CHANGELOG.md following Keep a Changelog, covering 0.1.0 and 0.2.0
- server/version.js reads the version from package.json; /healthz returns it
  and the footer renders it, so a deployment always states what it is serving
- bump package.json 0.1.0 -> 0.2.0

server/views/layout.js

@@ -1,3 +1,4 @@
+import { VERSION } from '../version.js';
 import { esc } from '../http.js';
 
 export function layout({ title, body, state = null, script = null, bodyClass = '', admin = null, nav = '' }) {
@@ -22,7 +23,7 @@ export function layout({ title, body, state = null, script = null, bodyClass = '
 <main>
 ${body}
 </main>
-<footer class="foot">Courtside · self-hosted tournament desk · <a href="https://gitea.cloudfreeiot.com/bkvargyas/courtside">source</a></footer>
+<footer class="foot">Courtside v${VERSION} · self-hosted tournament desk · <a href="https://gitea.cloudfreeiot.com/bkvargyas/courtside">source</a></footer>
 ${state ? `<script id="state" type="application/json">${JSON.stringify(state).replace(/</g, '\\u003c')}</script>` : ''}
 ${script ? `<script src="${esc(script)}" defer></script>` : ''}
 </body>