fix(amazonq): Language server overrides should reference assets directly

[jpinkney-aws]

Problem

The language server initialization logic incorrectly handles custom server paths. When users specify a custom language server location through an environment variable, the code still appends servers/aws-lsp-codewhisperer.js to the path, leading to incorrect server resolution.

Solution

When a custom language server path is provided via environment variable (indicated by location === 'override'), use the specified asset directory path directly instead of appending the default server path. This allows users to have full control over the language server location.

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[github-actions]

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