Replace additional internal APIs with public alternatives

- CachedImageIcon.getUrl() -> Class.getResource() for icon URLs
- TestStateInfo.Magnitude.getValue() -> SMTestProxy.getMagnitude()
- BaseState.intIncrementModificationCount() -> incrementModificationCount()
- EduMacroMap.hashCode() - add comment that it's required abstract override

Reduces internal API usages from 91 to 85.

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

Author: meanmail

intellij-plugin/hs-core/src/org/hyperskill/academy/learning/checker/tests/SMTestResultCollector.kt

@@ -83,7 +83,7 @@ open class SMTestResultCollector : TestResultCollector() {
   protected fun SMTestProxy.toEduTestInfo(name: String, message: String, diff: CheckResultDiff?): EduTestInfo {
     return EduTestInfo(
       name = name,
-      status = magnitudeInfo.value,
+      status = magnitude,
       message = removeAttributes(fillWithIncorrect(message)),
       details = stacktrace,
       isFinishedSuccessfully = finishedSuccessfully(),

intellij-plugin/hs-core/src/org/hyperskill/academy/learning/courseGeneration/macro/EduMacroMap.kt

@@ -2,9 +2,9 @@ package org.hyperskill.academy.learning.courseGeneration.macro
 
 import com.intellij.openapi.components.PathMacroMap
 
-@Suppress("EqualsOrHashCode")
 class EduMacroMap(private val mode: SubstitutionMode, private val macros: List<EduMacro>) : PathMacroMap() {
 
+  // PathMacroMap.hashCode() is abstract, must override
   override fun hashCode(): Int = macros.hashCode()
 
   override fun substitute(text: String, caseSensitive: Boolean): String {

intellij-plugin/hs-core/src/org/hyperskill/academy/learning/newproject/coursesStorage/CoursesStorageBase.kt

@@ -93,7 +93,7 @@ class UserCoursesState : BaseState() {
     if (courseMetaInfo != null) {
       courseMetaInfo.tasksSolved = tasksSolved
       courseMetaInfo.tasksTotal = tasksTotal
-      intIncrementModificationCount()
+      incrementModificationCount()
     }
     else {
       courses.add(JBACourseFromStorage(systemIndependentLocation, course, tasksTotal, tasksSolved))

intellij-plugin/hs-core/src/org/hyperskill/academy/learning/submissions/utils.kt

@@ -9,9 +9,7 @@ import com.intellij.openapi.fileEditor.FileDocumentManager
 import com.intellij.openapi.project.Project
 import com.intellij.openapi.vfs.VirtualFile
 import com.intellij.ui.ColorUtil
-import com.intellij.ui.icons.CachedImageIcon
 import com.intellij.util.Time
-import org.hyperskill.academy.EducationalCoreIcons.Submission.*
 import org.hyperskill.academy.learning.RemoteEnvHelper
 import org.hyperskill.academy.learning.courseDir
 import org.hyperskill.academy.learning.courseFormat.EduFormatNames.CORRECT
@@ -81,12 +79,14 @@ fun formatDate(time: Date): String {
 }
 
 fun getImageUrl(status: String?): URL? {
-  val icon = when (status) {
-    CORRECT -> if (StyleResourcesManager.isHighContrast()) TaskSolvedHighContrast else TaskSolved
-    else -> if (StyleResourcesManager.isHighContrast()) TaskFailedHighContrast else TaskFailed
-  }
+  val iconPath = when (status) {
+    CORRECT -> if (StyleResourcesManager.isHighContrast()) "/icons/org/hyperskill/academy/submission/taskSolvedHighContrast@2x.png"
+    else "/icons/org/hyperskill/academy/submission/taskSolved@2x.png"
 
-  return (icon as CachedImageIcon).url
+    else -> if (StyleResourcesManager.isHighContrast()) "/icons/org/hyperskill/academy/submission/taskFailedHighContrast@2x.png"
+    else "/icons/org/hyperskill/academy/submission/taskFailed@2x.png"
+  }
+  return Submission::class.java.getResource(iconPath)
 }
 
 fun getLinkColor(submission: Submission): String {