fix(amazonq): Add Open tab as params for inline completion

[leigaol]

Problem

aws/language-server-runtimes#638

The workspace.getAllTextDocuments() API only returns the open tabs that were clicked during this IDE session. If you open, close, reopen IDE, this API returns empty unless user re-click those files again.

So we need to let IDE compute the list of open tab files and send it to language server

Solution

Pass open tabs from the IDE to language server.
This is not customer facing so there is no change log needed.
It merely brings back old functional code.

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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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