Refactor README for consistency: remove emojis from section headers and update badge image paths

Author: remiceres

README.md

@@ -11,22 +11,22 @@
 
 [![License: CECILL-C](https://img.shields.io/badge/License-CECILL--C-blue.svg)](https://cecill.info/licences/Licence_CeCILL-C_V1-en.html) [![Discussions](https://img.shields.io/badge/Discussions-GitHub-blue)](https://github.com/orgs/corese-stack/discussions)
 
-## ✨ Features
+## Features
 
 - Convert RDF data formats (Turtle, RDF/XML, N-Triples, etc.)
 - Execute SPARQL queries on local or remote files
 - Query SPARQL endpoints
 - Validate RDF graphs using SHACL
 - Canonicalize RDF data
 
-## 🚀 Getting Started
+## Getting Started
 
 Install Corese-Command using your preferred platform:
 
 ### Linux
 
 <a href='https://flathub.org/apps/fr.inria.corese.CoreseCommand'>
-    <img width='140' alt='Get it on Flathub' src='https://flathub.org/api/badge?locale=en'/>
+    <img width='140' alt='Get it on Flathub' src='docs/source/_static/logo/badge_flathub.svg'/>
 </a>
 
 ```shell
@@ -53,16 +53,20 @@ You can also use Corese-Command as a standalone `.jar` file or add it to a Java
 
 > Requires Java 21 or higher.
 
-- [🔗 GitHub Releases](https://github.com/corese-stack/corese-command/releases)
-- [📦 Maven Central](https://central.sonatype.com/artifact/fr.inria.corese/corese-command)
+<a href='https://github.com/corese-stack/corese-command/releases'>
+    <img width='140' alt='Get it on GitHub' src='docs/source/_static/logo/badge_github.svg'/>
+</a>
+<a href='https://central.sonatype.com/artifact/fr.inria.corese/corese-command'>
+    <img width='140' alt='Get it on Maven Central' src='docs/source/_static/logo/badge_maven.svg'/>
+</a>
 
 Run manually with:
 
 ```shell
 java -jar corese-command-standalone.jar
 ```
 
-## ✅ Example Usage
+## Example Usage
 
 ```shell
 # Run a simple SPARQL query on an RDF file
@@ -89,19 +93,19 @@ corese canonicalize -i data.ttl -of rdfc-1.0-sha256
 corese query-endpoint -q 'SELECT * WHERE {?s ?p ?o}' -e "https://dbpedia.org/sparql"
 ```
 
-## 📖 Documentation
+## Documentation
 
 - [Getting Started Guide](https://corese-stack.github.io/corese-command/v4.6.1/user_guide.html)
 
-## 🤝 Contributing
+## Contributing
 
 We welcome contributions! Here’s how to get involved:
 
 - [GitHub Discussions](https://github.com/orgs/corese-stack/discussions)
 - [Issue Tracker](https://github.com/corese-stack/corese-command/issues)
 - [Pull Requests](https://github.com/corese-stack/corese-command/pulls)
 
-## 🔗 Useful Links
+## Useful Links
 
 - [Corese Website](https://corese-stack.github.io/corese-command/)
 - Mailing List: <corese-users@inria.fr>