feat: Add thousand separators and right-align numeric columns in debt table

[tryonlinux]

Improves readability of financial data by formatting currency values with commas and aligning all numeric columns to the right for easier comparison. Also adds CLAUDE.md documentation for future development.

🤖 Generated with Claude Code

Fixes #3

[github-actions]

✅ Test Results: PASSED

Test Output

=== RUN   TestCalculateMonthlyInterest
=== RUN   TestCalculateMonthlyInterest/Standard_credit_card_rate
=== RUN   TestCalculateMonthlyInterest/Zero_interest
=== RUN   TestCalculateMonthlyInterest/Low_interest_rate
=== RUN   TestCalculateMonthlyInterest/High_balance,_high_rate
--- PASS: TestCalculateMonthlyInterest (0.00s)
    --- PASS: TestCalculateMonthlyInterest/Standard_credit_card_rate (0.00s)
    --- PASS: TestCalculateMonthlyInterest/Zero_interest (0.00s)
    --- PASS: TestCalculateMonthlyInterest/Low_interest_rate (0.00s)
    --- PASS: TestCalculateMonthlyInterest/High_balance,_high_rate (0.00s)
=== RUN   TestProjectPayoffTimeline_SingleDebt
=== RUN   TestProjectPayoffTimeline_SingleDebt/No_snowball_amount
=== RUN   TestProjectPayoffTimeline_SingleDebt/With_snowball_amount
=== RUN   TestProjectPayoffTimeline_SingleDebt/Unpayable_debt_(payment_<_interest)
--- PASS: TestProjectPayoffTimeline_SingleDebt (0.00s)
    --- PASS: TestProjectPayoffTimeline_SingleDebt/No_snowball_amount (0.00s)
    --- PASS: TestProjectPayoffTimeline_SingleDebt/With_snowball_amount (0.00s)
    --- PASS: TestProjectPayoffTimeline_SingleDebt/Unpayable_debt_(payment_<_interest) (0.00s)
=== RUN   TestProjectPayoffTimeline_MultipleDebts_Snowball
--- PASS: TestProjectPayoffTimeline_MultipleDebts_Snowball (0.00s)
=== RUN   TestCalculateDebtFreeDate
=== RUN   TestCalculateDebtFreeDate/All_debts_payable
=== RUN   TestCalculateDebtFreeDate/One_unpayable_debt
--- PASS: TestCalculateDebtFreeDate (0.00s)
    --- PASS: TestCalculateDebtFreeDate/All_debts_payable (0.00s)
    --- PASS: TestCalculateDebtFreeDate/One_unpayable_debt (0.00s)
=== RUN   TestProjectPayoffTimeline_ZeroInterest
--- PASS: TestProjectPayoffTimeline_ZeroInterest (0.00s)
=== RUN   TestProjectPayoffTimeline_CascadingSnowball
--- PASS: TestProjectPayoffTimeline_CascadingSnowball (0.00s)
=== RUN   TestAddDebt
=== RUN   TestAddDebt/Add_debt_in_snowball_mode
=== RUN   TestAddDebt/Add_debt_in_manual_mode
=== RUN   TestAddDebt/Duplicate_creditor_name
--- PASS: TestAddDebt (0.00s)
    --- PASS: TestAddDebt/Add_debt_in_snowball_mode (0.00s)
    --- PASS: TestAddDebt/Add_debt_in_manual_mode (0.00s)
    --- PASS: TestAddDebt/Duplicate_creditor_name (0.00s)
=== RUN   TestGetAllDebts_Sorting
=== RUN   TestGetAllDebts_Sorting/Snowball_mode_sorting_(lowest_balance_first)
=== RUN   TestGetAllDebts_Sorting/Avalanche_mode_sorting_(highest_rate_first)
--- PASS: TestGetAllDebts_Sorting (0.00s)
    --- PASS: TestGetAllDebts_Sorting/Snowball_mode_sorting_(lowest_balance_first) (0.00s)
    --- PASS: TestGetAllDebts_Sorting/Avalanche_mode_sorting_(highest_rate_first) (0.00s)
=== RUN   TestUpdateDebtBalance
--- PASS: TestUpdateDebtBalance (0.00s)
=== RUN   TestRemoveDebt
--- PASS: TestRemoveDebt (0.00s)
=== RUN   TestRemoveDebt_NotFound
--- PASS: TestRemoveDebt_NotFound (0.00s)
=== RUN   TestUpdateDebtAPR
--- PASS: TestUpdateDebtAPR (0.00s)
=== RUN   TestSetManualOrdering
--- PASS: TestSetManualOrdering (0.00s)
=== RUN   TestClearManualOrdering
--- PASS: TestClearManualOrdering (0.00s)
=== RUN   TestSettings
=== RUN   TestSettings/Get_default_settings
=== RUN   TestSettings/Set_sort_mode
=== RUN   TestSettings/Set_snowball_amount
--- PASS: TestSettings (0.00s)
    --- PASS: TestSettings/Get_default_settings (0.00s)
    --- PASS: TestSettings/Set_sort_mode (0.00s)
    --- PASS: TestSettings/Set_snowball_amount (0.00s)
=== RUN   TestRecordPayment
=== RUN   TestRecordPayment/Record_payment_with_current_date
=== RUN   TestRecordPayment/Record_payment_with_specific_date
--- PASS: TestRecordPayment (0.00s)
    --- PASS: TestRecordPayment/Record_payment_with_current_date (0.00s)
    --- PASS: TestRecordPayment/Record_payment_with_specific_date (0.00s)
=== RUN   TestGetDebtByCreditor_CaseInsensitive
--- PASS: TestGetDebtByCreditor_CaseInsensitive (0.00s)
=== RUN   TestGetDebtByIndexOrName
=== RUN   TestGetDebtByIndexOrName/Get_by_index_-_snowball_mode
=== RUN   TestGetDebtByIndexOrName/Get_by_index_-_avalanche_mode
=== RUN   TestGetDebtByIndexOrName/Get_by_name
=== RUN   TestGetDebtByIndexOrName/Invalid_index
=== RUN   TestGetDebtByIndexOrName/Nonexistent_name
--- PASS: TestGetDebtByIndexOrName (0.00s)
    --- PASS: TestGetDebtByIndexOrName/Get_by_index_-_snowball_mode (0.00s)
    --- PASS: TestGetDebtByIndexOrName/Get_by_index_-_avalanche_mode (0.00s)
    --- PASS: TestGetDebtByIndexOrName/Get_by_name (0.00s)
    --- PASS: TestGetDebtByIndexOrName/Invalid_index (0.00s)
    --- PASS: TestGetDebtByIndexOrName/Nonexistent_name (0.00s)
=== RUN   TestGetAllDebts_HidesPaidDebts
--- PASS: TestGetAllDebts_HidesPaidDebts (0.00s)
=== RUN   TestResetDatabase
--- PASS: TestResetDatabase (0.00s)
PASS
ok  	github.com/tryonlinux/dave/tests	(cached)