fix(apply): run the page-count check Step 5b claimed Step 5d already ran (#476)

Step 5b's prose said "Page count is not checked here - that is
verify_pdf.py --pages's job, and Step 5d already runs it", and
verify_layout.py's docstring declines to measure page count for the same
reason. Step 5d's only verify_pdf.py call is --dump-text, and no step in
the workflow passed --pages at all (only the upstream-only CI assertion on
the stock examples does), so the hard 2-page CV and 1-page cover letter
limits were enforced by nothing but the visual PDF read - the "measure
first, then look" failure 5b was written to stop.

5b now runs verify_pdf.py --pages 2 on the CV and --pages 1 on the cover
letter ahead of verify_layout.py, names the ACTIVE-TEMPLATE page limit as
the substitute for a custom template, and the deferral sentence points at
those lines instead of at 5d.

tests/test_apply_page_count.py pins the invocations, their counts, their
order relative to the layout measurement, and that no prose defers the
check to a step that does not run it; all four cases fail on master.

tests/test_apply_page_count.py

@@ -0,0 +1,85 @@
+"""Guard for /apply Step 5b's page-count check.
+
+The 2-page CV and 1-page cover letter limits are the hard rules of
+05-cv-templates.md and 06-cover-letter-templates.md, and two places defer
+their enforcement to `tools/verify_pdf.py --pages`: `verify_layout.py`'s
+docstring ("page count is verify_pdf.py's job, and CI runs it") and Step 5b's
+own prose, which used to say "Step 5d already runs it". Step 5d's only
+invocation is `--dump-text`, and no other step passed `--pages` at all, so
+the one rule with a mechanical check had zero runnable implementations in
+the workflow. These tests pin that the invocations exist where the prose says
+they do, with the counts the guides require, and that no step defers the
+check to another step that does not run it.
+"""
+import re
+import unittest
+from pathlib import Path
+
+REPO = Path(__file__).resolve().parent.parent
+APPLY = REPO / ".claude" / "commands" / "apply.md"
+VERIFY_LAYOUT = REPO / "tools" / "verify_layout.py"
+
+
+def section(path, heading):
+    """The body of one markdown section, up to the next heading of any depth."""
+    text = path.read_text(encoding="utf-8")
+    start = text.index(heading) + len(heading)
+    rest = text[start:]
+    end = re.search(r"^#{1,4} ", rest, re.MULTILINE)
+    return rest[: end.start()] if end else rest
+
+
+def page_count_invocations(text):
+    """(document path, page count) for every runnable verify_pdf --pages line."""
+    return re.findall(
+        r"^python tools/verify_pdf\.py (\S+) --pages (\d+)\s*$", text, re.MULTILINE
+    )
+
+
+class ApplyRunsThePageCountCheck(unittest.TestCase):
+    def setUp(self):
+        self.step_5b = section(APPLY, "### 5b. Inspect layout")
+
+    def test_step_5b_checks_both_documents_with_the_guides_page_limits(self):
+        invocations = dict(page_count_invocations(self.step_5b))
+        self.assertEqual(
+            invocations.get("cv/main_<company>_<role>.pdf"),
+            "2",
+            "Step 5b must run verify_pdf.py --pages 2 on the CV - the hard "
+            "2-page limit has no other mechanical check",
+        )
+        self.assertEqual(
+            invocations.get("cover_letters/cover_<company>_<role>.pdf"),
+            "1",
+            "Step 5b must run verify_pdf.py --pages 1 on the cover letter",
+        )
+
+    def test_page_count_runs_before_the_layout_measurement(self):
+        # verify_layout.py's own docstring declines to check page count because
+        # verify_pdf.py --pages does; the deferral only holds if that runs first.
+        first_pages = self.step_5b.index("--pages")
+        first_layout = self.step_5b.index("verify_layout.py")
+        self.assertLess(first_pages, first_layout)
+
+    def test_no_step_defers_the_check_to_a_step_that_does_not_run_it(self):
+        text = APPLY.read_text(encoding="utf-8")
+        self.assertNotIn(
+            "Step 5d already runs it",
+            text,
+            "Step 5d's only verify_pdf call is --dump-text; the page-count "
+            "invocation lives in 5b and the prose must point there",
+        )
+
+    def test_layout_tools_deferral_is_backed_by_a_runnable_invocation(self):
+        docstring = VERIFY_LAYOUT.read_text(encoding="utf-8")
+        self.assertIn("verify_pdf.py --pages", docstring)
+        self.assertGreaterEqual(
+            len(page_count_invocations(APPLY.read_text(encoding="utf-8"))),
+            2,
+            "verify_layout.py defers page count to verify_pdf.py --pages, so "
+            "/apply must actually invoke it",
+        )
+
+
+if __name__ == "__main__":
+    unittest.main()