fix(expenses): LAYAL CAFE $2.80 bug, United Airlines rotation & date

LAYAL CAFE ($2.80 instead of $42.90):
- Add (?!\s*tax) lookahead to _TOTAL_RE so "Total Taxes $2.80" is never
  confused with the receipt total when OCR drops the "Taxes" word
- Change Pass 1 from matches[-1] to max() so the largest labeled amount
  always wins, regardless of line order in the OCR output

United Airlines (Subway/$0/wrong date):
- Add OSD-based rotation correction in receipt_parser.py: after EXIF
  transpose, ask Tesseract's orientation-detection engine (--psm 0) what
  angle to rotate; applies to receipts photographed lying sideways where
  EXIF metadata cannot help
- Add month-name date patterns (DD MON YYYY / MON DD YYYY) to
  _extract_date_from_text for airline/hotel receipts that print dates
  like "05 MAY 2026" instead of "05/07/26"

85 tests, all passing.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

tests/test_expenses_agent.py

@@ -428,6 +428,7 @@ async def test_act_no_employee_returns_empty_and_escalates():
 
 from agent_service.agents.expenses_agent import (
     _extract_amount_from_text, _extract_date_from_text, _is_likely_bank_statement,
+    _MONTH_MAP,
 )
 
 
@@ -473,6 +474,19 @@ class TestExtractAmount:
         text = 'Items  5.00\nTax 0.50\nTotal\n5.50'
         assert _extract_amount_from_text(text) == 5.50
 
+    def test_total_taxes_excluded(self):
+        # "Total Taxes $2.80" must NOT be confused with the receipt total;
+        # the labeled-total regex excludes 'total tax/taxes' via lookahead.
+        text = 'Subtotal $40.10\nTotal Taxes $2.80\nTotal $42.90'
+        assert _extract_amount_from_text(text) == 42.90
+
+    def test_pass1_returns_max_not_last(self):
+        # If OCR garbles "Total Taxes" into "Total\n$2.80", _TOTAL_RE would
+        # accidentally match twice.  max() must win over positional [-1].
+        # Simulate by giving two labeled totals where smaller appears second.
+        text = 'Grand Total $42.90\nTotal $2.80'
+        assert _extract_amount_from_text(text) == 42.90
+
     def test_total_sale_gas_station(self):
         # Costco / Shell gas receipts say "Total Sale $X.XX", not "Total: $X.XX"
         text = 'Pump  9  16.189 Gal\nRegular  $ 58.75\nTotal Sale  $ 58.75'
@@ -566,6 +580,20 @@ class TestExtractDate:
     def test_us_short_year(self):
         assert _extract_date_from_text('05/09/26') == '2026-05-09'
 
+    def test_dd_mon_yyyy(self):
+        # Airline / hotel receipts: "05 MAY 2026", "Issue Date: 05 May 2026"
+        assert _extract_date_from_text('Issue Date: 05 MAY 2026 MIA A70') == '2026-05-05'
+
+    def test_mon_dd_yyyy(self):
+        assert _extract_date_from_text('MAY 05 2026') == '2026-05-05'
+
+    def test_mon_dd_comma_yyyy(self):
+        assert _extract_date_from_text('May 5, 2026') == '2026-05-05'
+
+    def test_month_map_completeness(self):
+        # All twelve three-letter abbreviations must be present
+        assert len({k for k in _MONTH_MAP if len(k) == 3}) == 12
+
     def test_no_date(self):
         assert _extract_date_from_text('No date here') is None