Release 0.2.21; track the StartOS version files

Cut version 0.2.21 (current = v_0_2_21) with the adjudicated DO-item fixes.
Also commits the previously-untracked v_0_2_* version files that
versions/index.ts imports (ROADMAP item D2), so a fresh checkout builds
without dangling imports. The missing v_0_2_2 is intentional (versions are
an unordered set).

Built and verified: ten31portal_x86_64.s9pk packs cleanly at 0.2.21:0,
arch x86_64, SDK 0.4.0.

deploy/package.json

@@ -1,6 +1,6 @@
 {
   "name": "ten31portal-startos",
-  "version": "0.2.20",
+  "version": "0.2.21",
   "private": true,
   "scripts": {
     "build": "npm run check && rm -rf ./javascript && ncc build startos/index.ts -o ./javascript",