fix(amazonq): migrate process.env proxy setting handling to proxyUtil.ts

[samgst-amazon]

Problem

Previous fix was separate from the existing proxyUtil.ts handling.

Solution

Logic has been moved form platform.ts to proxyUtil.ts to have all process.env handling in one place.
also added fetching for NO_PROXY settings from vsc

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[github-actions]

• This pull request modifies code in src/* but no tests were added/updated.
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[tsmithsz]

Do we need to update the proxyUtil to use the new env variables?: https://github.com/tsmithsz/language-server-runtimes/blob/main/runtimes/runtimes/util/standalone/proxyUtil.ts