docs: redesign home page (index.md) and improve structure and clarity

Author: bsayli

.gitignore

@@ -46,6 +46,8 @@ Thumbs.db
 # =========================
 # Maven
 # =========================
+# Maven flattened pom
+.flattened-pom.xml
 pom.xml.tag
 pom.xml.releaseBackup
 pom.xml.versionsBackup

docs/index.md

@@ -130,7 +130,7 @@ The exact same contract type flows from server to client.
 ### Before (default OpenAPI behavior)
 
 <p align="center">
-  <img src="/openapi-generics/docs/images/proof/generated-client-wrapper-before.png" width="700"/>
+  <img src="docs/images/proof/generated-client-wrapper-before.png" width="700"/>
 </p>
 
 * duplicated envelope per endpoint
@@ -142,7 +142,7 @@ The exact same contract type flows from server to client.
 ### After (contract-aligned generation)
 
 <p align="center">
-  <img src="/openapi-generics/docs/images/proof/generated-client-wrapper-after.png" width="700"/>
+  <img src="docs/images/proof/generated-client-wrapper-after.png" width="700"/>
 </p>
 
 ```java