feat: Improve DX when developing against another repo (#831)

* feat: Add new start:yalc script

* chore: Exclude tests and build dirs from declarations

* chore: Don't emit types from base tsconfig

* fix: Make sure declarations are updated correctly with tsdx watch

There is an issue with some tsdx dependencies (the rollup typescript plugin)
that causes ts declarations to not be rebuilt when running tsdx.

See rollup/plugins#418

* fix: Specify CSS extract file

* doc: Update doc for developing w/ Reactist

* fix: Remove vestigial sentence and fix backticks

README.md

@@ -88,36 +88,55 @@ This boots up a development server with hot reloading on http://localhost:6006.
 
 ## Inside your application
 
-For the second development mode you can leverage `npm link`. First run:
+For the second development mode you can leverage `npm start:yalc`. First, make sure you have `yalc` installed globally:
+
+```shell
+npm install -g yalc
+```
+
+Then, in the reactist repository run:
 
 ```sh
-npm run start
+npm run start:yalc
 ```
 
-this will update the build artifacts whenever you change something.
+this will publish Reactist to `yalc` and watch for changes.
 
-In your real application you need to first delete the current _@doist/reactist_ dependency and then link to your local one.
+In your host application you can then link to your local Reactist version:
 
 ```sh
 cd ~/your-app
-# delete current reactist dependency
-rm -rf ./node_modules/@doist/reactist
-
-# link local reactist version
-npm link ../reactist
+yalc add @doist/reactist
 ```
 
-The relative path to reactist may need to be changed to match your local environment.
-
-To undo the changes and switch back to the reactist version from npm do the following:
+To undo the changes and switch back to the reactist version from npm, do the following:
 
 ```sh
 cd ~/your-app
-# first remove linked reactist dependency
-rm -rf ./node_modules/@doist/reactist
+# restore the original reactist version
+yalc remove @doist/reactist
+# re-install reactist from npm
+npm install
+```
+
+For convenience, you can add a `dev:reactist` script in your host application to automate the process of adding and removing the local Reactist version:
+
+```json5
+{
+    // ...
+    scripts: {
+        // ...
+        'predev:reactist': 'yalc add @doist/reactist',
+        'dev:reactist': 'npm run dev', // or whatever your development script is
+        'postdev:reactist': 'yalc remove @doist/reactist && npm i',
+    },
+}
+```
 
-# re-install reactist from npm (-E avoids updating the version / package-lock.json)
-npm install -E @doist/reactist
+Then, to develop against Reactist, just run:
+
+```sh
+npm run dev:reactist
 ```
 
 ## Development tips and tricks