fix(ledger): one-line CSS rules fingerprint their own declarations; the proposer writes uses edges for judged rows too (#2872, #2870)

First deploy of v26.08.21.1 showed two gaps:
- Every one-line CSS rule followed by a blank line hashed to sha1("") — the
  declarations live on the selector line, which the #2872 "declarations only"
  fingerprint dropped — so 68 unrelated one-liners across 17 files read as
  one body-identical copy at the top of the derive readout. The selector
  line's tail after "{" is now part of the hash; an all-blank remainder falls
  back to the whole block.
- The proposer only examined unjudged rows, so consumers that were already
  classified (auth.create_invitation → hash_token) never got a uses edge: 3
  edges for hash_token after the first refresh. Judged rows are now scanned
  for references (once per body), no proposal is made on them.
- 0084 migration docstring reworded: "function that …" at a line start parsed
  as a definition (extractor false positive).

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

tests/test_pattern_coverage.py

@@ -481,6 +481,13 @@ def test_extract_definitions_fingerprints_each_block():
     css = ".closed-msg {\n  text-align: center;\n  padding: 0.5rem 0;\n}\n.error-block {\n  text-align: center;\n  padding: 0.5rem 0;\n}\n.other {\n  text-align: left;\n}\n"
     d = {x.name: x for x in extract_definitions(css)}
     assert d["closed-msg"].body_sha == d["error-block"].body_sha != d["other"].body_sha
+    # One-line rules hash their own declarations — never the empty string
+    # (first deploy grouped 68 unrelated one-liners as one copy).
+    one = ".a { color: red; }\n\n.b { color: red; }\n\n.c { color: blue; }\n\n.d {\n  color: red;\n}\n"
+    e = {x.name: x for x in extract_definitions(one)}
+    import hashlib
+    assert e["a"].body_sha == e["b"].body_sha != e["c"].body_sha
+    assert e["a"].body_sha != hashlib.sha1(b"").hexdigest()[:16]
 
 
 def test_coverage_line_names_the_proposers_standing():