fix: Fix app crash issue

[Kakueeen]

The length of the obtained text exceeds the maximum text length

Log: fix issue

[deepin-ci-robot]

deepin pr auto review

关键摘要:

• 在handleDocumentSemanticTokens函数中，对endPos和lineEndPos的比较应该使用>=而不是>来避免潜在的越界问题。
• sourceText的获取应该确保不会超出行的结束位置，以避免潜在的越界问题。
• cacheColumn变量在赋值时应该使用++而不是+=，以避免在循环中出现错误的行为。

是否建议立即修改:

• 是

[deepin-ci-robot]

[APPROVALNOTIFIER] This PR is NOT APPROVED

This pull-request has been approved by: Kakueeen, LiHua000
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