Refactor port constants to Placeholders.kt

Move SERVER_PORT and JDBC_PORT constants from Main.kt to Placeholders.kt to centralize configuration. This change improves maintainability by keeping related constants together in a single file. Additionally, it ensures that any updates to port configurations are managed more easily.

src/jvmMain/kotlin/nl/astraeus/tmpl/Main.kt

@@ -13,9 +13,6 @@ import nl.astraeus.tmpl.web.RequestHandler
 
 val log = Logger()
 
-val SERVER_PORT = 7001
-val JDBC_PORT = 8001
-
 fun main() {
   Thread.currentThread().uncaughtExceptionHandler = Thread.UncaughtExceptionHandler { t, e ->
     log.warn(e) {

src/jvmMain/kotlin/nl/astraeus/tmpl/Placeholders.kt

@@ -2,6 +2,9 @@ package nl.astraeus.tmpl
 
 val REPO_NAME = "dummy so the gitea template compiles, please remove"
 
+val SERVER_PORT = 7001
+val JDBC_PORT = 8001
+
 val pageTitle = "${REPO_NAME}"
 val itemUrl = "${REPO_NAME}"
 val repoName = "${REPO_NAME}"

src/jvmMain/kotlin/nl/astraeus/tmpl/web/Index.kt

@@ -8,6 +8,7 @@ import kotlinx.html.script
 import kotlinx.html.stream.appendHTML
 import kotlinx.html.title
 import nl.astraeus.tmpl.REPO_NAME
+import nl.astraeus.tmpl.itemUrl
 import nl.astraeus.tmpl.pageTitle
 import nl.astraeus.tmpl.repoName