fix(approvals): stop pushing a free-text predicate onto a masked payload snapshot (#11103)

* fix(approvals): stop pushing a free-text predicate onto a masked payload snapshot

The approval payload snapshot is redacted at serve time, per reader (#10749),
but `listRequests` / `countRequests` pushed a free-text disjunct onto the stored
column, which the driver evaluates unmasked. The field-level read controls
enforced on the way out therefore did not hold on the way in — declared, not
enforced. This extends the settled `maskingRule` posture (#8993) to the snapshot
column: a caller whose view of the snapshot is masked keeps free-text matching
on the four columns of `sys_approval_request` they read whole, and loses only
the snapshot disjunct.

The masked/unmasked verdict comes from the same authority and the same
per-caller call the serve path uses, asked as the caller — never a second,
independently derived notion of "redacted", since that drift is the defect one
layer down. Where serve declines to narrow (no authority wired, or a wired
authority answering "unresolvable"), the disjunct is kept: consistency with
serve, not blanket fail-closed.

Dropping a disjunct is strictly narrowing — no query is refused, nothing is
widened — and four disjuncts always remain, so the `$or` is never empty.

Part of #11040

* test(approvals): index the pushed-down predicate without `Array.prototype.at`

`lib` is ES2021 for this package, where `at` does not exist. The package's own
`typecheck` excludes `**/*.test.ts`, so the error surfaced only in the
`check:type-check-coverage --re-measure` ratchet, as TEST_DEBT 348 -> 349.

Fixed in the test rather than by growing the ledger or widening `lib`: the
ratchet is shrink-only, and the file needs no ES2022 library surface.

Part of #11040

---------

Co-authored-by: Claude <noreply@anthropic.com>

Author: os-warren

.changeset/approvals-free-text-not-over-masked-snapshot.md

@@ -0,0 +1,52 @@
+---
+"@objectstack/plugin-approvals": patch
+---
+
+**Deliberate search-semantics change.** `ApprovalService.listRequests` /
+`countRequests` no longer push a free-text predicate onto the payload snapshot
+column for a caller whose view of that snapshot is masked (#11040).
+
+Since #10749 the approval snapshot (`sys_approval_request.payload_json`, the
+submitted record's row) is redacted **at serve time, per reader**: each row is
+cut down to the fields that caller may read on that row's subject object. The
+full row deliberately stays at rest, so the approval record remains audit
+evidence of what was actually submitted.
+
+The free-text filter, however, is evaluated by the driver against the stored
+column — before anything is served, and therefore against the unmasked bytes. A
+predicate over that column is a question about its contents whose answer is row
+membership, so the field-level read controls #10749 enforces on the way out did
+not hold on the way in. That is `declared ≠ enforced`, and the platform has
+already settled the governing principle for it: under `maskingRule` (#8993) a
+field a caller sees masked is non-filterable, refused loudly, because otherwise
+equality probes reconstruct the hidden span. This extends that settled posture
+to the snapshot column, which is reached through a different door.
+
+**What changes.** For a caller whose view of the snapshot is masked, free-text
+search matches on `process_name`, `object_name`, `record_id` and `submitter_id`
+— the columns of `sys_approval_request` itself, which anyone who can see the row
+reads whole — and no longer on snapshot contents. Such a caller can still find a
+request by process, object, record id or submitter; they can no longer find one
+by a value they may not read. Rows returned, their order and pagination are
+otherwise untouched, and no query is refused: the change only ever removes one
+disjunct, never denies.
+
+**What does not change.** A caller the serve path hands the whole snapshot to
+keeps today's behaviour exactly — same rows, same order. That includes every
+deployment that has not wired a field-visibility authority (the seam is
+late-bound, and absent it snapshots are served unredacted), and the case where a
+wired authority declines to narrow. Consistency with the serve path is the rule
+here rather than blanket fail-closed: where serve hands over the whole snapshot,
+keeping the predicate discloses nothing serve does not already disclose.
+
+The masked/unmasked verdict is read from **the same authority and the same
+per-caller call the serve path uses**, asked as the caller. It is deliberately
+not a second, independently derived notion of "redacted" — two derivations drift,
+and the drift between a serve rule and a filter rule is exactly what this fixes.
+
+Because redaction is decided per row while a filter is built before any row
+exists, the predicate-time scope matters: with an `object` filter the subject
+object is known and the seam is asked about it directly; without one the query
+spans every object, nothing sound can be asked, and the disjunct is dropped.
+
+Held by `approval-free-text-scope.test.ts`.