Adds EIS info to Security billing

[jmikell821]

Addresses #967.

NOTE: We aren't ready to publish these updates yet, so I commented out the paragraph that adds this info and will merge the PR so we'll have the content for when we're ready to publish.

[gaurav-elastic]

Hi @shubhaat , @jamesspi , this ticket is to add EIS information to the security billing dimensions page. Two questions :

1. Since we have paused the rollout to more customers, should we still proceed to add this information on this page or wait? (considering that we have already rolled it out to 11 customers and have no plans to rollback afaik).
2. Is the name 'Elastic Managed LLM' finalised? If so, we should replace 'Elastic LLM' on this page with the former.
   cc @chrisdistasio

[jamesspi]

@gaurav-elastic correct - we should wait on this for now. And yes, "Elastic Managed LLM" is finalized.

[gaurav-elastic]

@benironside @jmikell821 as James confirmed above, please pause these changes until the outstanding issues have been resolved and we can continue the rollout of EIS.
Please also replace all occurrences of 'Elastic LLM' with 'Elastic Managed LLM' in the text.

[jmikell821]

@gaurav-elastic @jamesspi spelling/grammar nit: It should technically be Elastic-managed LLM — let me know if that's acceptable. :)

Also, I'll comment out the paragraph, that way when we're ready to publish this, the content will already be there.

[gaurav-elastic]

@jmikell821, the PLI, or what is shown on the billing usage page is still called 'Elastic Inference Service'. Only the dropdown for Elastic LLM when selecting the LLM in AI Assistant or Attack Discovery is now called Elastic Managed LLM (or Elastic-managed LLM, until James or Shubha confirm). So I recommend that the title of this section be called something like 'Elastic Inference Service - Elastic Managed LLM'. In the body we could replace "default LLM" with "default Elastic Managed LLM."

[jmikell821]

Thanks @gaurav-elastic. Since I've merged the PR, I've added a note to #967 as a reminder for when we're ready to publish this.