Add/update FAQs for user guide

[selbigmtnwx23]

DESCRIPTION OF CHANGES:

Adding new and updating old FAQ's

Type of change

• [ X] This change requires a documentation update

TESTS CONDUCTED:

N/A

DEPENDENCIES:

DOCUMENTATION:

ISSUE:

https://jira.epic.oarcloud.noaa.gov/browse/USS-632
https://confluence.epic.oarcloud.noaa.gov/spaces/ECE/pages/403636545/ECE+2026-03-18+ECP+Update+PI19+New+Technical+FAQs+and+Update+Existing

CHECKLIST

• [ X] My code follows the style guidelines in the Contributor's Guide
• [ X] I have performed a self-review of my own code using the Code Reviewer's Guide
• [ X] I have commented my code, particularly in hard-to-understand areas
• [ X] My changes need updates to the documentation. I have made corresponding changes to the documentation
• [ X] My changes do not require updates to the documentation (explain).
• [ X] My changes generate no new warnings
• [ X] New and existing tests pass with my changes
• [ X] Any dependent changes have been merged and published

LABELS (optional):

A Code Manager needs to add the following labels to this PR:

• [ X] documentation

[gspetro-NOAA]

Merged via #3203 .