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>

alembic/versions/0084_code_shape_uses.py

@@ -5,9 +5,9 @@ Revises: 0083
 Create Date: 2026-08-21
 
 A ledger row carries ONE snippet_id: what shape this is (instance/variant of
-a canon). But a shape can also CALL several canonical helpers — a service
-function that is an instance of the service-function convention and a
-consumer of hash_token. The 2026-08 audit had to pick one; hook evidence
+a canon). But a shape can also CALL several canonical helpers — e.g. a
+service function both conforming to the service-function convention and
+consuming hash_token. The 2026-08 audit had to pick one; hook evidence
 ("pulled #N then wrote code referencing it") was stamped as instance when it
 is a uses fact. This table holds the many-valued relation: shape → snippet,
 with the basis and the evidence. Cascades with the shape and the snippet.