add logic to allow separate var including students who exit on frist day

[rlittle08]

Description & motivation

New config: edu:enroll:first_day_exit_date_inclusive

Background

Two existing vars interact when filtering out students who never really attended:

• edu:enroll:exclude_exit_before_first_day (default: True) — drops enrollments where the student exited before the first school day
• edu:enroll:exit_withdraw_date_inclusive (default: True) — controls whether exit dates are treated as inclusive (<=) or exclusive (<) throughout enrollment logic

When an implementation sets exit_withdraw_date_inclusive: False, the first-day exit check inherits that exclusivity — meaning a student who exited on the first day of school is treated the same as one who exited the day before and gets dropped.

The problem

exit_withdraw_date	first_school_day	exit_withdraw_date_inclusive	included?
Aug 25 (first day)	Aug 25	True	✅ kept
Aug 25 (first day)	Aug 25	False	❌ dropped
Aug 24 (day before)	Aug 25	True	❌ dropped
Aug 24 (day before)	Aug 25	False	❌ dropped
Aug 26 (day after)	Aug 25	True	✅ kept
Aug 26 (day after)	Aug 25	False	✅ kept

Implementations using exclusive exit dates lose first-day attendees even though that's not the intent of the filter.

The fix

A new var edu:enroll:first_day_exit_date_inclusive controls inclusivity for only the first-day exit check. It defaults to whatever exit_withdraw_date_inclusive is set to (preserving existing behavior), but can be set independently.

exit_withdraw_date_inclusive	first_day_exit_date_inclusive	first-day exit result
True (default)	not set (inherits True)	✅ kept
False	not set (inherits False)	❌ dropped
False	True	✅ kept

Usage

Implementations that use exclusive exit dates but want to retain students who exited on the first day can add to dbt_project.yml:

vars:
  'edu:enroll:exit_withdraw_date_inclusive': False
  'edu:enroll:first_day_exit_date_inclusive': True

Breaking changes introduced by this PR:

None

PR Merge Priority:

• Low
• Medium
• High

Changes to existing files:

New files created:

Tests and QC done:

Ran in SC, did quick check --

select * from dev_analytics.dev_rl_wh.fct_student_school_association
where k_student not in (select k_student from analytics.prod_wh.fct_student_school_association)
-- uncomment this to prove that all the student's we're adding exited on the first day of school
-- and k_student not in (select k_student from analytics.prod_stage.stg_ef3__student_school_associations
--                         join analytics.prod_build.bld_ef3__school_calendar_windows
--                           using(k_school_calendar)
--                         where exit_withdraw_date = first_school_day 
--                         )
;

Needs deeper QC on wider warehouse impacts

edu_wh PR Review Checklist:

Make sure the following have been completed before approving this PR:

• Description of changes has been added to Unreleased section of CHANGELOG.md. Add under ## New Features for features, etc.
• Code has been tested/checked for Databricks and Snowflake compatibility - EA engineers see Databricks checklist here
• Reviewer confirms the grain of all tables are unchanged, OR any changes are expected, communicated, and this PR is flagged as a breaking change (not for patch release)
• If a new configuration xwalk was added:
  • The code is written such that the xwalk is optional (preferred), and this behavior was tested, OR
  • The code is written such that the xwalk is required, and the required xwalk is added to edu_project_template, and this PR is flagged as breaking change (not for patch release)
  • A description for the new xwalk has been added to EDU documentation site here
• If a new configuration variable was added:
  • The code is written such that the variable is optional (preferred), and this behavior was tested, OR
  • The code is written such that the variable is required, and a default value was added to edu_project_template, and this PR is flagged as breaking change (not for patch release)
  • A description for the new variable has been added to EDU documentation site here