docs: use dynamic version attributes in SwingBridge documentation

Replace hardcoded version numbers with AsciiDoc attributes from
_vaadin-version.adoc so they stay in sync with platform updates.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

Author: taefi

articles/_vaadin-version.adoc

@@ -5,3 +5,4 @@
 :vaadin-seven-version: 7.7.49
 :vaadin-eight-version: 8.28.4
 :spring-boot-version: 4.0.4
+:swing-bridge-version: 1.1.1

articles/tools/modernization-toolkit/swing-bridge.adoc

@@ -6,6 +6,8 @@ meta-description: Learn how to install and use SwingBridge
 order: 140
 ---
 
+include::{articles}/_vaadin-version.adoc[]
+
 = [since:com.vaadin:vaadin@V25.1]#SwingBridge#
 
 pass:[<!-- vale Vaadin.ProductName = NO -->]
@@ -117,19 +119,19 @@ The `applibs` directory name is case-sensitive. To use a custom directory, pass
 Add the following parent section, properties, and dependencies to your `pom.xml`:
 
 .`pom.xml`
-[source,xml]
+[source,xml,subs="+attributes"]
 ----
 <properties>
   <maven.compiler.source>21</maven.compiler.source>
-  <vaadin.version>25.1.0</vaadin.version>
-  <swing-bridge.version>1.1.0</swing-bridge.version>
-  <swing-bridge.path>${settings.localRepository}/com/vaadin</swing-bridge.path>
+  <vaadin.version>{vaadin-version}</vaadin.version>
+  <swing-bridge.version>{swing-bridge-version}</swing-bridge.version>
+  <swing-bridge.path>$\{settings.localRepository}/com/vaadin</swing-bridge.path>
 </properties>
 
 <parent>
   <groupId>org.springframework.boot</groupId>
   <artifactId>spring-boot-starter-parent</artifactId>
-  <version>4.0.4</version>
+  <version>{spring-boot-version}</version>
   <relativePath/>
 </parent>
 
@@ -138,7 +140,7 @@ Add the following parent section, properties, and dependencies to your `pom.xml`
     <dependency>
       <groupId>com.vaadin</groupId>
       <artifactId>vaadin-bom</artifactId>
-      <version>${vaadin.version}</version>
+      <version>$\{vaadin.version}</version>
       <type>pom</type>
       <scope>import</scope>
     </dependency>
@@ -149,17 +151,17 @@ Add the following parent section, properties, and dependencies to your `pom.xml`
   <dependency>
     <groupId>com.vaadin</groupId>
     <artifactId>swing-bridge-patch</artifactId>
-    <version>${swing-bridge.version}</version>
+    <version>$\{swing-bridge.version}</version>
   </dependency>
   <dependency>
     <groupId>com.vaadin</groupId>
     <artifactId>swing-bridge-graphics</artifactId>
-    <version>${swing-bridge.version}</version>
+    <version>$\{swing-bridge.version}</version>
   </dependency>
   <dependency>
     <groupId>com.vaadin</groupId>
     <artifactId>swing-bridge-flow</artifactId>
-    <version>${swing-bridge.version}</version>
+    <version>$\{swing-bridge.version}</version>
     <exclusions>
       <exclusion>
         <groupId>org.apache.logging.log4j</groupId>