[2.x] fix: Support inline comments in .jvmopts and .sbtopts files (#8758)

**Problem**
After PR #8730 (commit 921efce), inline comments in .jvmopts and .sbtopts files cause errors.
For example, `--add-opens=java.base/java.util=ALL-UNNAMED # comment` results in:
Error: Could not find or load main class #

The # and everything after it is now parsed as separate arguments instead of being stripped as a comment.

**Solution**
Update the sed command in outputConfigFileTokens() to strip inline comments (everything from # to end of line) before parsing tokens.

The new s/\s*\#.*// pattern matches optional whitespace + # + rest of line and removes it.

Generated-by: Claude Sonnet 4.5

launcher-package/integration-test/src/test/scala/RunnerScriptTest.scala

@@ -309,4 +309,40 @@ object RunnerScriptTest extends verify.BasicTestSuite with ShellScriptUtil:
       s"Should not have shell expansion errors, but found: ${errorMessages.mkString(", ")}"
     )
 
+  // Test for issue #8755: Inline comments should be supported in .jvmopts
+  testOutput(
+    "sbt with inline comments in .jvmopts",
+    jvmoptsFileContents =
+      "--add-opens=java.base/java.util=ALL-UNNAMED # This is an inline comment\n-Dtest.key=value # Another comment",
+    windowsSupport = false,
+  )("-v"): (out: List[String]) =>
+    // Verify that options are present (comments should be stripped)
+    assert(
+      out.contains[String]("--add-opens=java.base/java.util=ALL-UNNAMED"),
+      "Option with inline comment should be parsed correctly"
+    )
+    assert(
+      out.contains[String]("-Dtest.key=value"),
+      "System property with inline comment should be parsed correctly"
+    )
+    // Verify comments themselves are NOT present as separate arguments
+    assert(
+      !out.exists(_.contains("This is an inline comment")),
+      "Inline comment should not appear in command line"
+    )
+    assert(
+      !out.exists(_.contains("Another comment")),
+      "Inline comment should not appear in command line"
+    )
+    // Verify no "command not found" errors for '#' character
+    val errorMessages = out.filter(line =>
+      line.contains("Could not find or load main class #") ||
+        line.contains("command not found") ||
+        line.contains("was unexpected")
+    )
+    assert(
+      errorMessages.isEmpty,
+      s"Should not have errors from comment character, but found: ${errorMessages.mkString(", ")}"
+    )
+
 end RunnerScriptTest

sbt

@@ -805,7 +805,7 @@ outputConfigFileTokens() {
   local file="$1"
   [[ ! -f "$file" ]] && return
   while IFS= read -r line || [[ -n "$line" ]]; do
-    line=$(printf '%s' "$line" | sed $'/^\#/d;s/\r$//')
+    line=$(printf '%s' "$line" | sed $'/^\#/d;s/\s*\#.*//;s/\r$//')
     [[ -z "$line" ]] && continue
     if [[ "$line" == -J* ]]; then
       local rest="${line#-J}"