feat(amazonq): add a opt-in checkbox for server-side context

[LiGaCu]

Problem

In order to open workspace context server to all users, we need to support client-side opt-out.

Solution

Add a opt-in checkbox for server-side context

Tested together with the aws/language-servers change:

• feat(amazonq): allow opt-out for workspace context server language-servers#1867

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[github-actions]

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