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>

src/scribe/services/coverage.py

@@ -191,7 +191,19 @@ def extract_definitions(text: str) -> list[Definition]:
         # same rule under another name?" — .closed-msg / .error-block /
         # .success-msg with identical bodies are one dup group, not three
         # lonely rows. Sym blocks keep their signature line in the hash.
-        hashed = block[1:] if kind == "css" and len(block) > 1 else block
+        if kind == "css":
+            # One-line rules (`.x { color: red; }`) carry their declarations on
+            # the selector line itself; a block that is only the selector plus
+            # trailing blanks must not hash to the empty string (which grouped
+            # 68 unrelated one-liners as one "copy" on first deploy, #2872).
+            first = lines[i]
+            brace = first.find("{")
+            head = [first[brace + 1:]] if brace >= 0 and first[brace + 1:].strip() else []
+            hashed = head + block[1:]
+            if not any(x.strip() for x in hashed):
+                hashed = block
+        else:
+            hashed = block
         out.append(Definition(
             kind, name, lines[i].strip()[:_SIGNATURE_CAP], _block_sha(hashed),
             "\n".join(block), i,