feat: add composer create + begin collections

Author: neothone

content/for-admin-users/collections.mdx

@@ -1 +1,13 @@
-This documentation page about collections feature will be available later...
+# Collections
+
+Collections are a way to group related items together for easier management and access. They can be used to organize content, products, or any other type of data that needs to be categorized.
+
+Collections can be created, edited, and deleted by admin users.
+
+A collection can contain multiple items, named Records.
+
+Records can be added to or removed from a collection as needed.
+
+---
+
+__This documentation page about collections feature will be completed later...__

content/for-developers/install-start.mdx

@@ -2,6 +2,25 @@
 
 ## Create new project
 
+### With Composer
+
+You can create a new Fastfony project using Composer. We recommend creating a new development project on a local development machine and follow the [Go to production](for-developers/go-to-production) instructions to deploy it on a production server.
+
+With this method, no Git repository is created by default. You can initialize a Git repository later if needed.
+
+1. Open your terminal and navigate to the directory where you want to create your Fastfony project.
+2. Run the following command to create a new Fastfony project:
+```bash
+composer create-project fastfony/fastfony your-project-name
+```
+Replace `your-project-name` with the desired name for your project directory.
+3. Navigate to the newly created project directory:
+```bash
+cd your-project-name
+```
+
+### or with Github template
+
 We recommend creating a new development project on a local development machine and follow the [Go to production](for-developers/go-to-production) instructions to deploy it on a production server.
 
 1. Go on [Fastfony Github template link ](https://github.com/new?template_name=fastfony&template_owner=fastfony) in order to create your own repository from the template.

content/for-developers/specific-things.mdx

@@ -1,4 +1,4 @@
 # Specific things
 
 - Translation files are not in `./translations` directory but in `./assets/locales` directory in order to use [vue-i18n](https://vue-i18n.intlify.dev/) and symfony translation component. We try to apply [php-translation best practices](https://php-translation.readthedocs.io/en/latest/best-practice/index.html).
-- In directories `pro` or `Pro` you can find the pro features of Fastfony. You can use them if you have a license. If you don't have a license, you can use only in development mode.
+