[IntelliJ] Uncaught Exception Error retrieving vulnerability data from GitHub Security Advisory API java.net.ConnectException

IntelliJ build version: 2025.3.2 IU-253.30387.90
OS: Linux
JDK: JetBrains s.r.o. 21.0.9
Plugin version: 3.97.1-2025.3
Additional Info: None
Parent component:

com.intellij.openapi.wm.impl.IdeRootPane[,0,0,1920x1028,layout=com.intellij.openapi.wm.impl.IdeRootPane$CustomHeaderRootLayout,alignmentX=0.0,alignmentY=0.0,border=,flags=449,maximumSize=,minimumSize=,preferredSize=]

Error message:

IdeaLoggingEvent[message=Error retrieving vulnerability data from GitHub Security Advisory API, throwable=java.net.ConnectException
	at <REDACTED: user-file-path>(HttpClientImpl.java:955)
	at com.microsoft.azure.toolkit.intellij.appmod.javaupgrade.service.CVECheckService.retrieveVulnerabilityData(CVECheckService.java:312)
	at com.microsoft.azure.toolkit.intellij.appmod.javaupgrade.service.CVECheckService.fetchCves(CVECheckService.java:241)
	at com.microsoft.azure.toolkit.intellij.appmod.javaupgrade.service.CVECheckService.getCveUpgradeIssues(CVECheckService.java:200)
	at com.microsoft.azure.toolkit.intellij.appmod.javaupgrade.service.CVECheckService.batchGetCVEIssues(CVECheckService.java:171)
	at com.microsoft.azure.toolkit.intellij.appmod.javaupgrade.service.JavaUpgradeIssuesDetectionService.getCVEIssues(JavaUpgradeIssuesDetectionService.java:385)
	at com.microsoft.azure.toolkit.intellij.appmod.javaupgrade.service.JavaUp

Start in CVECheckService.java at retrieveVulnerabilityData, then trace fetchCves, getCveUpgradeIssues, and batchGetCVEIssues from the provided stack trace. Reproduce the GitHub Security Advisory API request if possible and determine how the ConnectException is surfaced. Done should mean the reported connection failure is handled without an uncaught IntelliJ error, with tests covering the behavior if existing tests are found.