docs: Move react-email to dev dependencies in install guides (#1522)

Author: PCRinus

apps/docs/getting-started/manual-setup.mdx

@@ -27,15 +27,18 @@ Install the React Email package locally and a few components.
 <CodeGroup>
 
 ```sh npm
-npm install react-email @react-email/components -E
+npm install react-email -D -E
+npm install @react-email/components -E
 ```
 
 ```sh yarn
-yarn add react-email @react-email/components -E
+yarn add react-email -D -E
+yarn add @react-email/components -E
 ```
 
 ```sh pnpm
-pnpm add react-email @react-email/components -E
+pnpm add react-email -D -E
+pnpm add @react-email/components -E
 ```
 
 </CodeGroup>

apps/docs/getting-started/monorepo-setup/npm.mdx

@@ -24,7 +24,8 @@ Include a new `package.json` and do not forget to add this to the `workspaces` o
 Install React Email in the `transactional` workspace.
 
 ```sh packages/transactional
-npm install react-email @react-email/components -E
+npm install react-email -D -E
+npm install @react-email/components -E
 ```
 
 ## 3. Add scripts

apps/docs/getting-started/monorepo-setup/pnpm.mdx

@@ -23,7 +23,8 @@ in there setup a new `package.json` and do not forget to add this to your `pnpm-
 Install React Email in the `transactional` workspace.
 
 ```sh packages/transactional
-pnpm add react-email @react-email/components -E
+pnpm add react-email -D -E
+pnpm add @react-email/components -E
 ```
 
 ## 3. Add scripts

apps/docs/getting-started/monorepo-setup/yarn.mdx

@@ -39,7 +39,8 @@ nodeLinker: node-modules
 Install React Email in the `transactional` workspace.
 
 ```sh packages/transactional
-yarn add react-email @react-email/components -E
+yarn add react-email -D -E
+yarn add @react-email/components -E
 ```
 
 ## 4. Add scripts