De-slop pass: dead plumbing out, comments stop narrating history

Eric asked whether AI residue had crept in since the last credibility
pass. It had, in two forms — both descendants of the audit's
"row-edit flow is collid-exact now" fix, which corrected upload.py but
not everyone who believed the old constraint:

The deferral scaffolding survived its own removal: build_queue still
returned a permanently-empty deferred list, run_upload still unpacked
it and carried a dead echo branch repeating the DISPROVEN claim ("the
row-edit flow can't target a collid"). And diff.py held a vestigial
guard on the same false premise, refusing to upgrade a versionless
copy whenever a sibling carried a version and telling the human to do
it by hand — the collid-exact editor makes that upgrade safe, so the
guard cost a real capability and its test now pins the opposite.

A comment audit (13 findings, verified line-by-line) cleaned the rest:
the webreview docstring counted six pages of seven and claimed
"localhost only" (--lan exists); the nav comment still said "catalog"
for the page renamed Titles; extract's docstring credited "Claude
vision" though any OpenAI-compatible endpoint dispatches; and five
comments narrated retired bugs ("the original bug", "why the old
guess quit after page one", "made the count go negative") — each
rewritten as the present-tense constraint or trimmed, per the
standing rule: comments state what the code can't show, never how it
got that way.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_016jXZFSTZQKzAC8fqpWSz9g

tests/test_diff.py

@@ -192,13 +192,14 @@ def test_earlier_disagreement_cannot_steal_a_later_rows_exact_match():
     assert result.disagreements == []
 
 
-def test_update_withheld_when_another_copy_is_versioned():
-    # upload's row edit targets by NAME: an update is only safe when every
-    # copy is versionless, else it could overwrite the versioned copy
+def test_versionless_copy_upgrades_even_beside_a_versioned_sibling():
+    # the update flow is collid-exact, so the versioned copy (collid 900)
+    # is never at risk: the versionless one (collid 901) takes the upgrade
     rows = [_match("Catan", "13", vstatus="version_auto", vid="5", vname="5th")]
     result = compute_diff(rows, [_item(13, 900, version_id=7), _item(13, 901)])
-    assert result.to_update == []
-    assert "set it by hand" in result.disagreements[0]
+    (update,) = result.to_update
+    assert update["collid"] == "901" and update["version_id"] == "5"
+    assert result.disagreements == []
 
 
 def test_bare_row_does_not_steal_versionless_copy_from_confident_update():