feat(amazonq): Disable Q agentic commands not supported in SageMaker apps and skip agentic welcome prompt

[parameja1]

Problem

SageMaker AI and Unified Studio currently in prod uses version 1.32 and with manual upgrade to the newer version >1.54, observing agentic prompt added along with new commands /test, /review, /doc which are not supported by SageMaker apps

Solution

1. SageMaker doesnt support currently /dev, /transform commands and in addition to that disabling the above listed agentic Q commands that are not supported in SageMaker apps(both SMAI and SMUS).
2. Also disabling the agentic options from quick pick items
3. Skip agentic welcome prompt

Testing
npm run compile && npm run package and tested with the artefacts manually in SMUS and SMAI

• Treat all work as PUBLIC. Private feature/x branches will not be squash-merged at release time.
• Your code changes must meet the guidelines in CONTRIBUTING.md.
• License: I confirm that my contribution is made under the terms of the Apache 2.0 license.

[github-actions]

• This pull request modifies code in src/* but no tests were added/updated.
  • Confirm whether tests should be added or ensure the PR description explains why tests are not required.

[justinmk3]

👍 This is done for Toolkit here:

aws-toolkit-vscode/packages/core/src/extensionNode.ts

Lines 124 to 129 in 191c504

	if (!isSageMaker()) {
	await setContext('aws.isSageMaker', false)
	await codecatalyst.activate(extContext)
	} else {
	await setContext('aws.isSageMaker', true)
	}

but currently packages/amazonq/src/extension.ts does not share a "common" startup logic w/ Toolkit, so we need this redundant code here.

[parameja1]

Ack, thanks for adding the details Justin