Expose template registry and drop rollup-plugin-ts

[vscav]

Can be reviewed commit by commit.

Context

This PR aims at improving the TypeScript experience and aligning with the last best practice.

How

First, we now expose the template-registry of the Lottie component. It allows proper template typing in consuming applications using TypeScript with a Glint setup (see how-to from Glint).

Then, we propose to move off rollup-plugin-ts, following the latest guidelines from addon-blueprint (see PR for details). Note that in our case, using rollup-plugin-ts, it became impossible to build the addon locally (and so impossible to test it locally in consuming applications). Now the type declarations will be outputted in a separate declarations folder inside the build folder.

Examples

Wrong argument

Wrong type

Tasks

• Upgrade glint dependencies
• Export component template-registry
• Move off rollup-plugin-ts
• Add script to run linter for Glint
• Add documentation for users wanting to use the addon in an Ember application set up with TS
• Use yalc to test the addon (build and usage) locally in both JS and TS ember applications

[SkoebaSteve]

LGTM, this is a welcome improvement!