fix(amazonq): support inline completion in notebook

[leigaol]

Problem

The inline completion in Jupyter Notebook is not working. https://github.com/aws/aws-toolkit-vscode/pull/7086/files is gone after inline completion migration to language server.

Solution

1. Re-implement inline completion in Notebook
2. Re-organize the left and right context given precise cursor position in current cell.

Requires aws/language-servers#2114

---

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[amazon-inspector-ohio]

⏳ I'm reviewing this pull request for security vulnerabilities and code quality issues. I'll provide an update when I'm done

[github-actions]

• This pull request modifies code in src/* but no tests were added/updated.
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[amazon-inspector-ohio]

✅ I finished the code review, and didn't find any security or code quality issues.