Refactor OH TANF structure and simplify income aggregation

**Structure Improvements:**
- Organize variables into eligibility/ and income/ subfolders
- Organize parameters into income/deductions/ subfolder
- Follows pattern from PA TANF implementation (PR #6764)

**Simplifications:**
- Remove state-specific earned income variable
- Remove income/earned.yaml parameter list
- Directly aggregate employment_income + self_employment_income
- Use federal tanf_gross_unearned_income variable
- Update parameter path: income.deductions.earned_income_disregard

**Files Deleted:**
- oh_tanf_gross_earned_income.py (no longer needed)
- income/earned.yaml (use federal sources directly)

**Files Moved:**
Variables:
- oh_tanf_eligible.py → eligibility/
- oh_tanf_income_eligible.py → eligibility/
- oh_tanf_countable_income.py → income/

Parameters:
- earned_income_disregard.yaml → income/deductions/

All 63 tests still passing.

Author: hua7450

policyengine_us/parameters/gov/states/oh/odjfs/tanf/earned_income_disregard.yaml renamed to policyengine_us/parameters/gov/states/oh/odjfs/tanf/income/deductions/earned_income_disregard.yaml

@@ -14,29 +14,34 @@ class oh_tanf_countable_income(Variable):
     )
 
     def formula(spm_unit, period, parameters):
-        # Get gross earned income
-        gross_earned = spm_unit("oh_tanf_gross_earned_income", period)
+        person = spm_unit.members
+
+        # Get gross earned income - aggregate from federal sources
+        gross_earned = spm_unit.sum(
+            person("employment_income", period)
+            + person("self_employment_income", period)
+        )
 
         # Apply earned income disregard: $250 + 50% of remainder
         # ORC 5107.10(D)(3) specifies "the two hundred-fifty dollar and
         # one-half of the remainder disregards"
-        p = parameters(period).gov.states.oh.odjfs.tanf.earned_income_disregard
-        flat_disregard = p.flat_amount
+        p = parameters(period).gov.states.oh.odjfs.tanf.income.deductions
+        disregard = p.earned_income_disregard
+        flat_disregard = disregard.flat_amount
 
         # Calculate remainder after flat disregard
         remainder = max_(gross_earned - flat_disregard, 0)
 
         # Apply percentage disregard to remainder
-        percent_disregarded = remainder * p.percent_of_remainder
+        percent_disregarded = remainder * disregard.percent_of_remainder
 
         # Countable earned income = gross - flat disregard - percent of remainder
         countable_earned = max_(
             gross_earned - flat_disregard - percent_disregarded, 0
         )
 
-        # Get gross unearned income
+        # Get gross unearned income from federal variable
         # Per ORC 5107.10(D)(3): "No disregards apply to gross unearned income"
-        person = spm_unit.members
         gross_unearned = spm_unit.sum(
             person("tanf_gross_unearned_income", period)
         )

policyengine_us/parameters/gov/states/oh/odjfs/tanf/income/earned.yaml

@@ -29,8 +29,9 @@ def formula(spm_unit, period, parameters):
         # Apply minimum benefit threshold
         # Per OAC 5101:1-23-40: "OWF shall not be authorized when the
         # amount is at least $1 but less than $10 per month"
-        p = parameters(period).gov.states.oh.odjfs.tanf
-        minimum_benefit = p.minimum_benefit
+        minimum_benefit = parameters(
+            period
+        ).gov.states.oh.odjfs.tanf.minimum_benefit
 
         # If benefit is positive but below minimum, set to zero
         benefit_meets_minimum = (benefit >= minimum_benefit) | (benefit <= 0)