Fix crash when parsing native stack frames without symbols

[BartoszLitwiniuk]

Summary

Fixes a crash in the native stack trace parser when frames are missing symbol information. Refactors BacktraceRawStackTraceParser for safer parsing and adds unit test coverage.

It's a follow up of changes made in #258 and bug BT-5953.

Changes

• Added bounds checks in SetNativeStackTraceInformation to prevent out-of-range access when a native frame lacks symbol data
• Extract parsing logic to BacktraceRawStackTraceParser for clearer, more defensive frame parsing
• Added debug logging to aid future diagnosis of malformed frames
• Added BacktraceRawStackTraceParserTests covering native frame parsing edge cases
• Use BacktraceRawStackTraceParser in BacktraceUnhandledException instead of mixing unhandled exception handler with parsing logic

Testing

• New unit tests validate safe parsing of native frames, including frames without symbols
• Existing tests continue to pass

[melekr]

can you link sample BT reports @BartoszLitwiniuk ?

[melekr]

how about :

Suggested change

	private BacktraceStackFrame TryParseFrameOrFallback(string frame)
	private BacktraceStackFrame TryParseFrameOrFallback(string frame)
	{
	try
	{
	string frameString = frame.Trim();
	if (frameString.StartsWith("0x", StringComparison.Ordinal))
	{
	return ParseNativeFrame(frameString);
	}
	if (frameString.StartsWith("#", StringComparison.Ordinal))
	{
	return SetJITStackTraceInformation(frameString);
	}
	int methodNameEndIndex = frameString.IndexOf(')');
	if (methodNameEndIndex == -1)
	{
	return new BacktraceStackFrame
	{
	FunctionName = frame,
	InvalidFrame = true
	};
	}
	int openParentIndex = frameString.LastIndexOf('(', methodNameEndIndex);
	if (openParentIndex == -1 || openParentIndex > methodNameEndIndex)
	{
	return new BacktraceStackFrame
	{
	FunctionName = frame,
	InvalidFrame = true
	};
	}
	return ParseStacktraceFrame(frameString, methodNameEndIndex);
	}
	catch
	{
	return new BacktraceStackFrame
	{
	FunctionName = frame,
	InvalidFrame = true
	};
	}
	}

[melekr]

lgtm.

let's add the tests as discussed.