fix(salary): convert the IDA workbook again ("Firmanavn og by" header) and list unreachable in the scrape schema (#615)

"firma" joins COMPOUND_PATTERNS so the glued Danish header "Firmanavn og by"
matches again; whole-token matching since #75 skipped both sheets of the
repository's own demonstration workbook with "Could not find header row".
Every other workbook converts byte-identically. Also folds the `unreachable`
status from #564 into the seen_jobs.json schema enum in the scrape spec.

Co-authored-by: Claude Fable 5.1 <noreply@anthropic.com>

tests/test_convert_salary_excel.py

@@ -7,6 +7,7 @@ from salary_lookup import format_entry
 from tools.convert_salary_excel import (
     INDEX_PATTERNS,
     detect_column_type,
+    COMPANY_PATTERNS,
     header_matches,
     parse_numeric_cell,
     parse_sheet,
@@ -108,6 +109,22 @@ class DetectColumnTypeTests(unittest.TestCase):
                     companies[0]["categories"]["salary"], {"index": 105.5}
                 )
 
+    def test_parse_sheet_detects_danish_compound_company_header(self):
+        # The IDA workbook heads its company column "Firmanavn og by": "firma"
+        # glued to "navn". Whole-token matching alone skipped the entire sheet
+        # ("Could not find header row") from #75 until "firma" joined
+        # COMPOUND_PATTERNS, so the shipped demonstration data no longer
+        # converted at all.
+        self.assertTrue(header_matches("Firmanavn og by", COMPANY_PATTERNS))
+        ws = FakeWorksheet([
+            ("Firmanavn og by", "Antal", "Indeks"),
+            ("Example A/S, Aarhus", 12, 105.0),
+        ])
+        companies = parse_sheet(ws)
+        self.assertEqual(len(companies), 1)
+        self.assertEqual(companies[0]["company"], "Example A/S, Aarhus")
+        self.assertEqual(companies[0]["categories"]["all_employees"], {"count": 12, "index": 105.0})
+
     def test_parse_sheet_detects_city_column_with_token_header(self):
         # City headers are matched with the same token-based header_matches()
         # used for the company column, not exact string equality. Real-world