docs: replace deprecated maven-badges.herokuapp.com and dead search.maven.org URLs (#592)

- Badge images: maven-badges.herokuapp.com/maven-central/<g>/<a>/badge.svg
  -> img.shields.io/maven-central/v/<g>/<a>.svg (Heroku free tier retired).
- Badge/artifact links: maven-badges.herokuapp.com/maven-central/<g>/<a>
  -> central.sonatype.com/artifact/<g>/<a>.
- Dead search.maven.org URLs with encoded g:/a: query params collapsed
  to the direct central.sonatype.com/artifact/<g>/<a> page.

Co-authored-by: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

Author: peter-lawrey

ReadMe.adoc

@@ -6,7 +6,7 @@ Chronicle Software
 :lang: en-GB
 :source-highlighter: rouge
 
-image:https://maven-badges.herokuapp.com/maven-central/net.openhft/chronicle-map/badge.svg[caption="",link=https://maven-badges.herokuapp.com/maven-central/net.openhft/chronicle-map]
+image:https://img.shields.io/maven-central/v/net.openhft/chronicle-map.svg[caption="",link=https://central.sonatype.com/artifact/net.openhft/chronicle-map]
 image:https://javadoc.io/badge2/net.openhft/chronicle-map/javadoc.svg[link="https://www.javadoc.io/doc/net.openhft/chronicle-map/latest/index.html"]
 //image:https://javadoc-badge.appspot.com/net.openhft/chronicle-map.svg?label=javadoc[JavaDoc, link=https://www.javadoc.io/doc/net.openhft/chronicle-map]
 image:https://img.shields.io/github/license/OpenHFT/Chronicle-Map[GitHub]

docs/CM_Download.adoc

@@ -25,8 +25,8 @@ If you want to obtain this software under a more permissive license, please cont
 == Maven Artifact Download
 
 [#image-maven]
-[caption="",link=https://maven-badges.herokuapp.com/maven-central/net.openhft/chronicle-map]
-image::https://maven-badges.herokuapp.com/maven-central/net.openhft/chronicle-map/badge.svg[]
+[caption="",link=https://central.sonatype.com/artifact/net.openhft/chronicle-map]
+image::https://img.shields.io/maven-central/v/net.openhft/chronicle-map.svg[]
 
 Chronicle Map depends on other Chronicle libraries and it is Chronicle's recommendation to use the
 https://chronicle.software/monorepo-versus-bill-of-materials-shaping-your-project/[chronicle-bom]
@@ -46,7 +46,7 @@ for versioning e.g.
 </dependencyManagement>
 ```
 
-Click here to get the https://search.maven.org/#search%7Cga%7C1%7Cg%3A%22net.openhft%22%20AND%20a%3A%22chronicle-bom%22[Latest Version Number].
+Click here to get the https://central.sonatype.com/artifact/net.openhft/chronicle-bom[Latest Version Number].
 
 Alternatively, Chronicle Map can be included directly:
 
@@ -58,7 +58,7 @@ Alternatively, Chronicle Map can be included directly:
 </dependency>
 ```
 
-Click here to get the https://search.maven.org/#search%7Cga%7C1%7Cg%3A%22net.openhft%22%20AND%20a%3A%22chronicle-map%22[Latest Version Number].
+Click here to get the https://central.sonatype.com/artifact/net.openhft/chronicle-map[Latest Version Number].
 
 == Maven Snapshot Download