Improvements in the README.md documentation and new BRANCHES.txt file.

[Marcos5399]

Description
This Pull Request introduces improvements to the Monica Personal CRM project's README, addressing concerns raised in various user-reported issues. New sections and subsections have been added to provide clearer information on key aspects of the repository, making it easier for new contributors to get involved.

Changes Made
The following changes have been implemented in response to issues reported by users and other documentation gaps identified:

✅ New "Next Updates" Section

1. Several issues referenced Chandler, but there was no mention of it in the project's documentation.

2. To address this lack of information, a new section has been created to provide context on Chandler and its relevance within the project.

✅ Subsections "How to Clone Git Repository" and "Command to Clone Git Repository"

1. Some users reported difficulties finding instructions on how to clone the repository in the main branch documentation.

2. In response, a subsection has been added with a direct link to the explanation of the git clone command within the project, along with a specific section providing the necessary command for cloning the repository.

✅ New "Branch Overview" Section

1. Although no specific issues were reported on this topic, we identified that the project's documentation does not specify the purpose of each branch, which may cause confusion for new contributors.

2. For example, deployment instructions are not in the main branch but in the 4.x branch, and this information is not documented anywhere.

3. To improve clarity, we have added this section to the README along with the BRANCHES.txt file, which documents the project's most important branches.

4. The community is invited to contribute additional information about the existing branches to keep the documentation updated and they can do it with the BRANCHES.txt file.

Motivation

These changes aim to enhance the clarity and usability of the official documentation, ensuring that new contributors have the necessary information to effectively participate in the project's development.

How to Review This Pull Request

📄 Review the modifications in README.md (the mentioned new sections and subsections).
📄 Check the BRANCHES.txt file, which has been added as part of this contribution.
BRANCHES.txt

Additional Comments

Suggestions and improvements to further optimize the project's documentation are welcome.

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