chore: use Nx affected tasks in CI (#5110)

Closes #5097

- Uses "nx affected" to detect what projects need to be checked in the
current PR (for now, `ci-front` and `ci-server` workflows only).
- Caches results of certain tasks (`lint`, `typecheck`, `test`,
`storybook:build`) when a PR pipeline runs. The next runs of the same
PR's pipeline will then be able to reuse the PR's task cache to execute
tasks faster.
- Caches Yarn's cache folder to install dependencies faster in CI jobs.
- Rewrites the node modules cache/install steps as a custom, reusable
Github action.
- Distributes `ci-front` jobs with a "matrix" strategy.
- Sets common tasks config at the root `nx.json`. For instance, to
activate the `typecheck` task in a project, add `typecheck: {}` to its
`project.json` and it'll use the default config set in `nx.json` for the
`typecheck` task. Options can be overridden in each individual
`project.json` if needed.
- Adds "scope" tags to some projects: `scope:frontend`, `scope:backend`,
`scope:shared`. An eslint rule ensures that `scope:frontend` only
depends on `scope:frontent` or `scope:shared` projects, same for
`scope:backend`. These tags are used by `nx affected` to filter projects
by scope and generates different task cache keys according to the
requested scope.
- Enables checks for twenty-emails in the `ci-server` workflow.

.github/workflows/actions/yarn-install/action.yaml

@@ -0,0 +1,23 @@
+name: Yarn Install
+
+runs:
+  using: "composite"
+  steps:
+    - name: Setup Node.js and get yarn cache
+      uses: actions/setup-node@v3
+      with:
+        node-version: "18"
+        cache: yarn
+    - name: Cache node modules
+      id: node-modules-cache
+      uses: actions/cache@v3
+      with:
+        path: |
+          node_modules
+          packages/*/node_modules
+        key: root-node_modules-${{ hashFiles('yarn.lock') }}
+        restore-keys: root-node_modules-
+    - name: Install Dependencies
+      shell: bash
+      run: yarn --immutable --check-cache
+      if: steps.node-modules-cache.outputs.cache-hit != 'true'