Feature - Add support for a fiscal year period defined in user settings.

* Add "This fiscal year", "Last fiscal year" as date range options in Transaction Details to filter transactions to those periods
* Add fiscal year ranges to Statistics & Trend Analysis
* Add "fiscal year start date" to user profile settings, allowing the user to select any date of the calendar year as the start of the fiscal year
* Add "fiscal year format" to user profile settings, allowing the user to specify how financial year date labels should appear

Implementation notes:
* The default fiscal year start is January 1 and the default fiscal year display format is "FY 2025"
* Fiscal year start date (month number & day number) are stored together in db as a uint16, high byte & low byte respectively
* February 29 is disallowed as a fiscal year start date, since it is never used as a convention in any country
* Jest is added to the project as a dev dependency, for unit tests in frontend

Signed-off-by: Sebastian Reategui <seb.reategui@gmail.com>

src/views/base/statistics/StatisticsTransactionPageBase.ts

@@ -37,6 +37,7 @@ export function useStatisticsTransactionPageBase() {
     const showAccountBalance = computed<boolean>(() => settingsStore.appSettings.showAccountBalance);
     const defaultCurrency = computed<string>(() => userStore.currentUserDefaultCurrency);
     const firstDayOfWeek = computed<number>(() => userStore.currentUserFirstDayOfWeek);
+    const fiscalYearStart = computed<number>(() => userStore.currentUserFiscalYearStart);
 
     const allDateRanges = computed<LocalizedDateRange[]>(() => {
         if (analysisType.value === StatisticsAnalysisType.CategoricalAnalysis) {
@@ -224,6 +225,7 @@ export function useStatisticsTransactionPageBase() {
         showAccountBalance,
         defaultCurrency,
         firstDayOfWeek,
+        fiscalYearStart,
         allDateRanges,
         allSortingTypes,
         allDateAggregationTypes,