feat(devx): read-seam invention rule gains an identity-pass-through criterion (#6451) (#6471)

The #5186 read-seam rule reddens on a `catch` around a storage read that logs
nothing and returns an invented answer. Its EMPTY value table (`[]` / `false` /
`null` / `undefined` / `{}` / `''` / `0` / `1`) could not see the shape #6116
turned out to be: `catch { return records; }`, where `records` is the enclosing
function's own parameter. That seam was counted in the census the whole time
while the gate printed a green line, so the defect survived under a gate that
had surveyed it — found by a human reading code, like the three before it.

Measured first, per the maintainer's 2026-08-06 收窄先行 ruling, before any
criterion was written. Across the three scan roots (78 production files, 292
catch clauses, 63 read seams) exactly 2 catches return one of their own
parameters; only 1 guards a read at all, and BOTH already log, so both are
absorbed by the existing "any log at all" exemption. The true new red set is
zero: this reddens nothing on `main` and adds no baseline entry.

The criterion is separate from the empty-value table on purpose —
`inventedEmptyValue` judges an expression alone, this one needs the enclosing
function's parameter list, and merging them would give the table a silent
context dependency. Both existing exemptions still apply unchanged, which is
why #6116's fixed seam stays green: it keeps passing the input through on both
branches and says so once.

- new `identityPassThrough` + `enclosingFunctionParameters`; findings carry a
  `kind` so the violation message names which criterion fired and offers the
  pass-through-specific fix (add one log; never "change the value")
- the census line now names the seam it used to render as "no invented answer"
- self-test: 8 new cases pinning #6116 before and after its fix, the
  type-discriminated branch, both-branch pass-through, a caller-supplied
  fallback, destructured/`as`/`!` spellings, a callback's own parameter, and
  the measured majority shape (an accumulated local is NOT a pass-through)
- new `expectInvents` assertion on the exact reported set: `expectViolation:
  false` is vacuous for cases that pass BECAUSE an exemption fired — deleting
  the criterion left them green, testing nothing. Reverse-verified: neutering
  the criterion turns 8 cases red, 2 of them solely through `expectInvents`
- limitation 4 records what the rule deliberately cannot do: separate
  "pass-through as declared contract" from "pass-through swallowing a fault"


Claude-Session: https://claude.ai/code/session_01BDmDsu2575gDxeMCxXhDE3

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

Author: hotlong