Refactor the create_federal_portfolio script

[zandercymatics]

Issue description

The create_federal_portfolio script has been evolving over time, but it is now becoming unwieldly to manage and hard to digest its output. Since we want to reuse this script in the future, the primary goal of this ticket is to rework this script such that it is more maintainable, readable, and more logical to follow when running the script.

Acceptance criteria

• The create_federal_portfolio script now logs created suborganizations, modified domain requests, and modified domain information objects rather than just displaying the change count for each
• The log output is cleaned up such that it is more readable than it currently is
• The script is reworked such that it is more modular and not as nested, so that we can easily gate certain abilities of the script behind flags in the future
• The script can now (in addition to ingesting branch and agency_name) a list of agency_names
• Any "post-process" steps are now accurately integrated inside of the main script

Additional context

This script has grew overtime from its original purpose. Initially, it was scoped to primarily just "creating" a singular federal portfolio record. At its current state, though, it now has the capability to parse through multiple records at once, at modify a lot of related data.

Links to other issues

No response