telemetry(amazonq): add an error code for when node validation fails.

[Hweinstock]

Problem

These errors show up in telemetry with reason Error. All of the reasonDesc are different since they include unique PID values. This makes it hard to count/quantify how often this is happening.

Solution

• attach a unique error code to these errors. For when node can't be run we have FailedToRunNode, and when the language server can't be started we have FailedToStartLanguageServer.

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[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.