Migrate to Ignition 8.3

[keith-gamble]

Summary

Moves the example module, its dev stack, CI and docs from Ignition 8.1.44 to 8.3.9.

8.3 no longer hot-swaps modules. Installs and upgrades apply only on gateway restart, and the developer upload servlet that deployModl posts to has been removed. This PR replaces that workflow.

Development loop

• Docker: ./gradlew build, then docker compose restart gateway. The module is auto-accepted on first boot through ACCEPT_MODULE_LICENSES / ACCEPT_MODULE_CERTS, including unsigned builds, so there is no commissioning to click through.
• Any 8.3 gateway: ./gradlew deployModule -PhostGateway=<url> -PignitionApiToken=<name:secret> uploads the module, accepts its certificate and license, and stages the install through the 8.3 REST API. Add -PrestartGateway=true to restart through /data/api/v1/restart-tasks/restart.
• Web assets still hot reload: with the -Dres.path.<moduleId> override and npm run watch, a refresh picks up JS and CSS changes.
• deployModl: the IA plugin still ships it, but it now fails fast with a pointer to deployModule.

Changes

• Build: SDK 8.3.9, requiredIgnitionVersion 8.3.0, io.ia.sdk.modl 0.5.0, Gradle 8.7, node-gradle 7.1.0. The Perspective jars are now compileOnly, so they are no longer bundled into the modl.
• Web: perspective-client 2.3.9. SizeObject moved to perspective-common and is now a type-only import. React is unchanged at 18.2.
• Java: no changes. The Perspective descriptor, registry, hook and resource-mount APIs this module uses have the same signatures in 8.3.
• Docker:
  • The image is ignition:8.3.9, configured from env vars.
  • The 8.1 gateway backup is removed.
  • GATEWAY_MODULES_ENABLED is an allowlist of fully-qualified ids in 8.3, so it lists this module.
  • Compose mounts the unsigned modl by default; set MODULE_FILE to mount the signed one.
• CI: actions/upload-artifact@v4 (v3 is blocked) and softprops/action-gh-release@v2 in place of the unmaintained release action.
• Docs:
  • The development loop, Docker setup, quick start, troubleshooting, build system and glossary pages cover 8.3.
  • A new "Upgrading from 8.1" reference page.
  • Links point at the 8.3 docs.
  • The Docker and build samples match the real files.
• The invalid JSON in the VS Code workspace file is fixed.

Testing

• ./gradlew clean build passes against SDK 8.3.9, and the modl contains only the module's own jars.
• On an ignition:8.3.9 container, the module starts with no commissioning, and /res/example-components/ExampleComponents.js is served.
• Edits to the mounted web output are served live.
• deployModule uploads the module and stages the install. After a restart through the API, the gateway reports the module ACTIVE with nothing quarantined.
• The Docusaurus build passes with onBrokenLinks: 'throw'.
• Not tested: the Designer (palette entry and icon) on 8.3, and the GitHub workflows, which run on this PR.