Report estimated resource usages as well as requested resources

# Summary

We currently report how much resource you requested * how long a your pod ran. This indicates the cost of your workflow. We should be able to use the metrics API to estimate how much you actually used.

# Motivation

Cost reduction. See #2972, #3089, #2934 .

# Proposal

See #2579

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**Message from the maintainers**:

If you wish to see this enhancement implemented please add a 👍 reaction to this issue! We often sort issues this way to know what to prioritize.

Start by reading the metrics API context and the proposal in issue #2579, along with the related cost-reduction issues #2972, #3089, and #2934. Done means workflow reporting includes estimated actual pod resource usage in addition to requested resources and runtime-based usage.

Written by the indexing model from the issue text.