CI does not compile test apps

[pmconne]

Describe the bug
The build scripts for apps like display-test-app and display-performance-test-app use vite build, not tsc. The latter reports errors that the former does not. Those errors then surface at run-time. This makes it possible to merge to master changes that do not compile, that can only be discovered when/if someone encounters the conditions which would cause the non-compiling code to execute.

To Reproduce
Steps to reproduce the behavior:

1. Pull itwinjs-core master branch as of the time of this issue.
2. rush build --to display-test-app.
3. Observe no compilation errors.
4. cd test-apps/display-test-app
5. npm run build:frontend
6. Observe compilation errors below. Note these various errors were introduced over the course of multiple separate PRs, waiting for someone to discover them.

npm run build:frontend

> [email protected] build:frontend
> tsc

src/frontend/DisplayScale.ts:13:10 - error TS2416: Property 'getModelDisplayTransform' in type 'DisplayScaleTransformProvider' is not assignable to the same property in base type 'ModelDisplayTransformProvider'.
  Type '(modelId: string) => Transform | undefined' is not assignable to type '(modelId: string) => ModelDisplayTransform | undefined'.
    Type 'Transform | undefined' is not assignable to type 'ModelDisplayTransform | undefined'.
      Property 'transform' is missing in type 'Transform' but required in type 'ModelDisplayTransform'.

13   public getModelDisplayTransform(modelId: string): Transform | undefined {
            ~~~~~~~~~~~~~~~~~~~~~~~~

  ../../core/frontend/lib/cjs/ViewState.d.ts:43:5
    43     transform: Transform;
           ~~~~~~~~~
    'transform' is declared here.

src/frontend/DisplayScale.ts:62:41 - error TS2345: Argument of type 'DisplayScaleTransformProvider' is not assignable to parameter of type 'ModelDisplayTransformProvider'.
  The types returned by 'getModelDisplayTransform(...)' are incompatible between these types.
    Type 'Transform | undefined' is not assignable to type 'ModelDisplayTransform | undefined'.
      Property 'transform' is missing in type 'Transform' but required in type 'ModelDisplayTransform'.

62     vp.setModelDisplayTransformProvider(tp);
                                           ~~

  ../../core/frontend/lib/cjs/ViewState.d.ts:43:5
    43     transform: Transform;
           ~~~~~~~~~
    'transform' is declared here.

src/frontend/DisplayTestApp.ts:189:28 - error TS2339: Property 'enableDiagnostics' does not exist on type 'RenderSystem'.

189     IModelApp.renderSystem.enableDiagnostics();
                               ~~~~~~~~~~~~~~~~~

src/frontend/DisplayTestApp.ts:210:30 - error TS2339: Property 'enableDiagnostics' does not exist on type 'RenderSystem'.

210       IModelApp.renderSystem.enableDiagnostics();
                                 ~~~~~~~~~~~~~~~~~

src/frontend/OutputShadersTool.ts:5:10 - error TS2305: Module '"@itwin/core-frontend"' has no exported member 'DebugShaderFile'.

5 import { DebugShaderFile, IModelApp, NotifyMessageDetails, OutputMessagePriority, Tool } from "@itwin/core-frontend";
           ~~~~~~~~~~~~~~~

src/frontend/TileContentTool.ts:18:44 - error TS2304: Cannot find name 'IModelTileTree'.

18   public override async run(args?: { tree: IModelTileTree, contentId: string }) {
                                              ~~~~~~~~~~~~~~

src/frontend/TileSizeRecorder.ts:8:21 - error TS2305: Module '"@itwin/core-frontend"' has no exported member 'IModelTileTree'.

8 import { IModelApp, IModelTileTree, TileAdmin, Tool } from "@itwin/core-frontend";
                      ~~~~~~~~~~~~~~

src/frontend/TiledGraphics.ts:60:10 - error TS2551: Property 'forEachModelTreeRef' does not exist on type 'ViewState'. Did you mean 'forEachTileTreeRef'?

60     view.forEachModelTreeRef((ref) => {
            ~~~~~~~~~~~~~~~~~~~

  ../../core/frontend/lib/cjs/ViewState.d.ts:289:5
    289     forEachTileTreeRef(func: (treeRef: TileTreeReference) => void): void;
            ~~~~~~~~~~~~~~~~~~
    'forEachTileTreeRef' is declared here.

src/frontend/TiledGraphics.ts:60:31 - error TS7006: Parameter 'ref' implicitly has an 'any' type.

60     view.forEachModelTreeRef((ref) => {
                                 ~~~


Found 9 errors in 6 files.

Errors  Files
     2  src/frontend/DisplayScale.ts:13
     2  src/frontend/DisplayTestApp.ts:189
     1  src/frontend/OutputShadersTool.ts:5
     1  src/frontend/TileContentTool.ts:18
     1  src/frontend/TileSizeRecorder.ts:8
     2  src/frontend/TiledGraphics.ts:60

Expected behavior
CI should fail if compilation errors exist.

Ideally, rush build will notify me of compilation errors locally as well, it is extremely annoying to edit code, run the app, and then discover a compilation error. The whole point of using a compiled language is to discover errors before running the code.

[tcobbs-bentley]

I would like to add here that the Android and iOS steps in the CI both compile and run display-test-app in a simulator/emulator. However, all they do is download a specific model from the hub, open that model, and wait for it to render the first time. So presumably the functionality that causes problems doesn't get exercised by that sequence.