fix: make maintainer tool output actionable

--emulator accepts a buildbot core name from a profile's cores:, and a
mistyped target gets the closest names instead of every target. diff_truth
shows destinations and reports unpaired entries as evidence, not removals.
The verify summary counts discrepancies, a shared destination names both
systems, a truth hash conflict names both cores, and pipeline steps carry
their place in the real run instead of N/8. Every GitHub API caller takes
the token from github_token(), which falls back to gh auth token.

tests/test_scraper_contract.py

@@ -664,6 +664,7 @@ class EveryGitHubApiCallerSendsTheToken(unittest.TestCase):
             if "api.github.com" in (source := path.read_text(encoding="utf-8"))
             and "GITHUB_TOKEN" not in source
             and "github_headers(" not in source
+            and "github_token(" not in source
         )
         self.assertEqual(silent, [])
 
@@ -690,6 +691,7 @@ class EveryGitHubApiCallerSendsTheToken(unittest.TestCase):
                     requests
                     and "api.github.com" in body
                     and "github_headers(" not in body
+                    and "github_token(" not in body
                     and "GITHUB_TOKEN" not in body
                 ):
                     silent.append(f"{path.relative_to(scripts)}:{node.name}")