Add a release-notes page linked from the footer version (v0.9.6)

Reconstructed from the commit history since the first production
deployment; the initial entry is the 0.9.0 port of the legacy bash
script to Kotlin/Spring Boot.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

src/main/kotlin/de/hoennig/gittally/server/UiController.kt

@@ -109,6 +109,13 @@ class UiController(
         return "current"
     }
 
+    /** Hand-maintained release notes (templates/releases.html); linked from the version in the footer. */
+    @GetMapping("/releases")
+    fun releases(model: Model): String {
+        baseModel(model, view = "releases", pageTitle = "Release Notes")
+        return "releases"
+    }
+
     @GetMapping("/system")
     fun system(model: Model): String {
         baseModel(model, view = "system", pageTitle = "System Metrics")