feat(amazonq): Automatically pause and resume @workspace indexing when OS CPU load is high

[leigaol]

Types of changes

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)

Description

If the customer machine is under heavy CPU load, the @workspace indexing can cause slowness.

When the user's OS is under heavy load, we pause the @workspace indexing and resumes when it is low. This is to avoid slowing down customer's device. If the customer opened multiple intelliJ instances at the same time while all these instances somehow starts vector indexing at the same time, then only the first 1 or 2 instances will get the CPU resource allocation while the others keeps waiting until the CPU load is down to a reasonable rate

Checklist

• My code follows the code style of this project
• I have added tests to cover my changes
• A short description of the change has been added to the CHANGELOG if the change is customer-facing in the IDE.
• I have added metrics for my changes (if required)

License

I confirm that my contribution is made under the terms of the Apache 2.0 license.