fix(java): give jdtls memory back when idle and stop it showing as not responding (#1137)

jdtls ran on the parallel collector, which never shrinks the heap while idle, so each server kept its import/build peak committed for as long as it lived. It now runs on G1 with a periodic collection every minute and a 10–30% free-heap band, so memory goes back to the OS once the work is done (a SkyWalking checkout: 1.9 GB → 1.25–1.3 GB idle). A collector set in the JVM options still replaces ours with its tuning; setting either heap-free ratio drops both of ours.

The Equinox launcher gets -nosplash: without it its native library loads AppKit on macOS and every jdtls shows as Not Responding in Activity Monitor.

Part of #1008.

src/features/settings/languages/LanguagePages.tsx

@@ -297,7 +297,7 @@ export function JavaPage() {
         <Row
           label="JVM options"
           htmlFor={id}
-          hint="Passed to the JVM running jdtls (java.jdt.ls.vmargs), e.g. -Xmx4g. jdtls runs with -XX:+UseParallelGC -XX:GCTimeRatio=4 -XX:AdaptiveSizePolicyWeight=90 -Xmx2G -Xms100m by default; an option set here replaces the default for the same setting, and another collector (e.g. -XX:+UseG1GC) replaces the default collector options. A Lombok agent is added automatically: the one installed in Language Servers, else, when the project uses Lombok (its build, an inherited parent POM or Gradle build, or its sources' imports), the newest from the Maven / Gradle caches."
+          hint="Passed to the JVM running jdtls (java.jdt.ls.vmargs), e.g. -Xmx4g. jdtls runs with -XX:+UseG1GC -XX:G1PeriodicGCInterval=60000 -XX:MinHeapFreeRatio=10 -XX:MaxHeapFreeRatio=30 -Xmx2G -Xms100m by default; an option set here replaces the default for the same setting, and another collector (e.g. -XX:+UseZGC) replaces the default collector options. A Lombok agent is added automatically: the one installed in Language Servers, else, when the project uses Lombok (its build, an inherited parent POM or Gradle build, or its sources' imports), the newest from the Maven / Gradle caches."
         >
           <Input
             id={id}

src/platform/locales/text/zh.json

@@ -1478,7 +1478,7 @@
   "Passed as -Dmaven.repo.local.": "以 -Dmaven.repo.local 传入。",
   "Passed as -s (mirrors, servers, proxies).": "以 -s 传入（镜像、服务器、代理）。",
   "Passed to rustfmt when reformatting, e.g. --edition 2024": "重新格式化时传递给 rustfmt，例如 --edition 2024",
-  "Passed to the JVM running jdtls (java.jdt.ls.vmargs), e.g. -Xmx4g. jdtls runs with -XX:+UseParallelGC -XX:GCTimeRatio=4 -XX:AdaptiveSizePolicyWeight=90 -Xmx2G -Xms100m by default; an option set here replaces the default for the same setting, and another collector (e.g. -XX:+UseG1GC) replaces the default collector options. A Lombok agent is added automatically: the one installed in Language Servers, else, when the project uses Lombok (its build, an inherited parent POM or Gradle build, or its sources' imports), the newest from the Maven / Gradle caches.": "传递给运行 jdtls 的 JVM (java.jdt.ls.vmargs)，例如 -Xmx4g。jdtls 默认使用 -XX:+UseParallelGC -XX:GCTimeRatio=4 -XX:AdaptiveSizePolicyWeight=90 -Xmx2G -Xms100m 运行；此处设置的选项会替换同一设置的默认值，指定其他垃圾回收器（例如 -XX:+UseG1GC）时会替换默认的回收器选项。会自动添加 Lombok 代理：优先使用在“语言服务器”中安装的版本；否则当项目使用 Lombok（构建文件、继承的父 POM 或 Gradle 构建、源码中的 import）时，使用 Maven / Gradle 缓存中最新的版本。",
+  "Passed to the JVM running jdtls (java.jdt.ls.vmargs), e.g. -Xmx4g. jdtls runs with -XX:+UseG1GC -XX:G1PeriodicGCInterval=60000 -XX:MinHeapFreeRatio=10 -XX:MaxHeapFreeRatio=30 -Xmx2G -Xms100m by default; an option set here replaces the default for the same setting, and another collector (e.g. -XX:+UseZGC) replaces the default collector options. A Lombok agent is added automatically: the one installed in Language Servers, else, when the project uses Lombok (its build, an inherited parent POM or Gradle build, or its sources' imports), the newest from the Maven / Gradle caches.": "传递给运行 jdtls 的 JVM (java.jdt.ls.vmargs)，例如 -Xmx4g。jdtls 默认使用 -XX:+UseG1GC -XX:G1PeriodicGCInterval=60000 -XX:MinHeapFreeRatio=10 -XX:MaxHeapFreeRatio=30 -Xmx2G -Xms100m 运行；此处设置的选项会替换同一设置的默认值，指定其他垃圾回收器（例如 -XX:+UseZGC）时会替换默认的回收器选项。会自动添加 Lombok 代理：优先使用在“语言服务器”中安装的版本；否则当项目使用 Lombok（构建文件、继承的父 POM 或 Gradle 构建、源码中的 import）时，使用 Maven / Gradle 缓存中最新的版本。",
   "Pop stash": "弹出储藏",
   "Preview Source": "预览源代码",
   "Reinstate index": "恢复索引",