build(versioning): synchronize app version across Tauri and simulation configs (#5120)

# Description of Changes

- **What was changed**
- Added `groovy.json.JsonOutput` and `groovy.json.JsonSlurper` imports
to `build.gradle`.
- Introduced a reusable `writeIfChanged(File targetFile, String
newContent)` helper to avoid unnecessary file writes when content is
unchanged.
  - Added `updateTauriConfigVersion(String version)` to:
    - Parse `frontend/src-tauri/tauri.conf.json`.
    - Set the `version` field from `project.version`.
- Re-write the file as pretty-printed JSON (with a trailing line
separator) only if content actually changed.
- Added `updateSimulationVersion(File fileToUpdate, String version)` to:
- Locate the `appVersion: '<value>'` assignment via regex in simulation
files.
    - Replace the existing version with `project.version`.
- Fail the build with a clear `GradleException` if `appVersion` cannot
be found.
- Registered a new Gradle task `syncAppVersion` (group: `versioning`)
which:
    - Reads `project.version` as the canonical app version.
    - Updates `frontend/src-tauri/tauri.conf.json`.
- Updates `frontend/src/core/testing/serverExperienceSimulations.ts`.
- Updates
`frontend/src/proprietary/testing/serverExperienceSimulations.ts`.
- Updated the main `build` task so it now depends on `syncAppVersion` in
addition to `:stirling-pdf:bootJar` and `buildRestartHelper`.

- **Why the change was made**
- To ensure the desktop Tauri configuration and server experience
simulation configs consistently use the same application version as
defined in `project.version`.
- To remove manual version bumps in multiple files and eliminate the
risk of version mismatches between backend, desktop app, and
simulation/testing tooling.
- To minimize noise in commits and CI by only touching versioned files
when their content actually changes (using `writeIfChanged`).


---

## Checklist

### General

- [ ] I have read the [Contribution
Guidelines](https://github.com/Stirling-Tools/Stirling-PDF/blob/main/CONTRIBUTING.md)
- [ ] I have read the [Stirling-PDF Developer
Guide](https://github.com/Stirling-Tools/Stirling-PDF/blob/main/devGuide/DeveloperGuide.md)
(if applicable)
- [ ] I have read the [How to add new languages to
Stirling-PDF](https://github.com/Stirling-Tools/Stirling-PDF/blob/main/devGuide/HowToAddNewLanguage.md)
(if applicable)
- [ ] I have performed a self-review of my own code
- [ ] My changes generate no new warnings

### Documentation

- [ ] I have updated relevant docs on [Stirling-PDF's doc
repo](https://github.com/Stirling-Tools/Stirling-Tools.github.io/blob/main/docs/)
(if functionality has heavily changed)
- [ ] I have read the section [Add New Translation
Tags](https://github.com/Stirling-Tools/Stirling-PDF/blob/main/devGuide/HowToAddNewLanguage.md#add-new-translation-tags)
(for new translation tags only)

### Translations (if applicable)

- [ ] I ran
[`scripts/counter_translation.py`](https://github.com/Stirling-Tools/Stirling-PDF/blob/main/docs/counter_translation.md)

### UI Changes (if applicable)

- [ ] Screenshots or videos demonstrating the UI changes are attached
(e.g., as comments or direct attachments in the PR)

### Testing (if applicable)

- [ ] I have tested my changes locally. Refer to the [Testing
Guide](https://github.com/Stirling-Tools/Stirling-PDF/blob/main/devGuide/DeveloperGuide.md#6-testing)
for more details.

build.gradle

@@ -12,6 +12,8 @@ plugins {
 }
 
 import com.github.jk1.license.render.*
+import groovy.json.JsonOutput
+import groovy.json.JsonSlurper
 
 ext {
     springBootVersion = "3.5.6"
@@ -65,6 +67,51 @@ allprojects {
     }
 }
 
+def writeIfChanged(File targetFile, String newContent) {
+    if (targetFile.getText('UTF-8') != newContent) {
+        targetFile.write(newContent, 'UTF-8')
+    }
+}
+
+def updateTauriConfigVersion(String version) {
+    File tauriConfig = file('frontend/src-tauri/tauri.conf.json')
+    def parsed = new JsonSlurper().parse(tauriConfig)
+    parsed.version = version
+
+    def formatted = JsonOutput.prettyPrint(JsonOutput.toJson(parsed)) + System.lineSeparator()
+    writeIfChanged(tauriConfig, formatted)
+}
+
+def updateSimulationVersion(File fileToUpdate, String version) {
+    def content = fileToUpdate.getText('UTF-8')
+    def matcher = content =~ /(appVersion:\s*')([^']*)(')/
+
+    if (!matcher.find()) {
+        throw new GradleException("Could not locate appVersion in ${fileToUpdate} for synchronization")
+    }
+
+    def updatedContent = matcher.replaceFirst("${matcher.group(1)}${version}${matcher.group(3)}")
+    writeIfChanged(fileToUpdate, updatedContent)
+}
+
+tasks.register('syncAppVersion') {
+    group = 'versioning'
+    description = 'Synchronizes app version across desktop and simulation configs.'
+
+    doLast {
+        def appVersion = project.version.toString()
+        println "Synchronizing application version to ${appVersion}"
+        updateTauriConfigVersion(appVersion)
+
+        [
+            'frontend/src/core/testing/serverExperienceSimulations.ts',
+            'frontend/src/proprietary/testing/serverExperienceSimulations.ts'
+        ].each { path ->
+            updateSimulationVersion(file(path), appVersion)
+        }
+    }
+}
+
 tasks.register('writeVersion', WriteProperties) {
     destinationFile = layout.projectDirectory.file('app/common/src/main/resources/version.properties')
     println "Writing version.properties to ${destinationFile.get().asFile.path}"
@@ -314,7 +361,7 @@ tasks.named('bootRun') {
 tasks.named('build') {
     group = 'build'
     description = 'Delegates to :stirling-pdf:bootJar'
-    dependsOn ':stirling-pdf:bootJar', 'buildRestartHelper'
+    dependsOn ':stirling-pdf:bootJar', 'buildRestartHelper', 'syncAppVersion'
 
     doFirst {
         println "Delegating to :stirling-pdf:bootJar"