feat(contributor-scan): name the function a question cannot locate (M1b 12.3)

After per-family context, every remaining unresolved question reported
context_scope_empty, all in three files. The cause is not a missing producer:
app/routes/index.js requires seven handler modules and defines none of them, so a
question naming handleContributionsUpdate there names a function that file
genuinely does not hold, and the empty scope is the correct answer.

Reporting that as "scope empty" hid which of two different things had happened. A
file the frontend produced no methods for is one problem; a question naming a
function defined in another module is another, and it is the common one. Taint and
configuration now separate them, reporting context_function_unresolved with the
name in the first case and context_scope_empty only when the file has no methods at
all. The driver no longer stacks its generic gap on top of a query that already
explained itself, and the new gap is question-owned so it cannot block another
question's comparison.

Completion is deliberately unchanged. The tempting fix is to widen such a question
to its whole file, which would raise the number by answering a question nobody
asked; a question whose function the graph does not hold stays unresolved, with the
name now recoverable from the question that asked it.

Group 12 is complete: admission no longer rejects genuine findings on a
mis-extracted operation symbol, both families that could never complete their change
context now can, and the remaining unresolved questions say precisely why.

1,406 tests passed, nine skipped.

Co-Authored-By: Claude Opus 5 (1M context) <[email protected]>
Claude-Session: https://claude.ai/code/session_01EmM1j46qgKMh3zqD1QMwEo

src/openultrasast/push/policy.py

@@ -320,6 +320,7 @@ def _context_boundaries(scan: ModelScanResult, *questions: QuestionIdentity) ->
     owned_prefixes = (
         "context_projection_unavailable:contributor-scan:",
         "context_scope_empty:contributor-scan:",
+        "context_function_unresolved:contributor-scan:",
         "dynamic_external_or_depth_context_unresolved:contributor-scan:",
     )
     retained = set(questions)