feat(fusion_accounting_reports): period picker wizard with common presets

Adds fusion.period.picker.wizard - a guided entry point that lets users
pick a report type and a common period preset (this/last month, quarter,
YTD, last year, or custom range). The wizard uses the existing date_periods
service helpers (month_bounds, quarter_bounds, fiscal_year_bounds) to
pre-fill date_from / date_to via @api.onchange.

action_open_report returns a client action that launches the OWL reports
viewer with default_report_type / default_date_from / default_date_to /
default_comparison in the context.

Tests: 3 new (test_period_picker.py). Net 111 -> 114.
Made-with: Cursor

fusion_accounting_reports/__manifest__.py

@@ -1,6 +1,6 @@
 {
     'name': 'Fusion Accounting Reports',
-    'version': '19.0.1.0.31',
+    'version': '19.0.1.0.32',
     'category': 'Accounting/Accounting',
     'summary': 'AI-augmented financial reports (P&L, balance sheet, trial balance, GL).',
     'description': """
@@ -38,6 +38,7 @@ menu hides; the engine and AI tools remain available for the chat.
         'data/cron.xml',
         'reports/report_pdf_template.xml',
         'wizards/xlsx_export_wizard_views.xml',
+        'wizards/period_picker_wizard_views.xml',
     ],
     'external_dependencies': {
         'python': ['xlsxwriter'],