fix(rust): a function type is a type alias, not a const's value

[gHashTag]

Closes #3364

master:  pub const Middleware: i32 = fn ( MiddlewareContext ) bool;
here:    pub type Middleware = fn(MiddlewareContext) -> bool;

The parser has no production for a function type — it swallows the whole text into one ExprIdentifier named "fn ( MiddlewareContext ) bool" — and the const emitter printed it as a value. C emits the same shape and Zig does not generate, so no neighbour answers this one; but nothing is being decided either, because a function type has exactly one Rust spelling and the current output is not an alternative to it.

Measured, two pinned binaries of distinct hashes over 650 specs: 352 OK both sides, zero regressions. +0. Exactly one spec changes output, server/http.t27, and it still fails — on expected expression, found \@`` underneath.

That underneath is the more useful finding. tri one-away reported this spec as carrying exactly one error; repairing it revealed the next. rustc abandons a file at the first parse error, so a sole uncoded diagnostic is a floor, not a total — the correction now folded into #3360 before it merges, which turns its headline from 50 into 24 exact and 26 lower bounds.

Narrow on purpose: = fn(...) also spells a closure with a body in two specs; those are values and are left alone.

[github-actions]

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[github-actions]

PR Dashboard

Generated at: 2026-09-06 06:20:05 UTC

• fix(rust): a function type is a type alias, not a const's value #3365 fix(rust): a function type is a type alias, not a const's value | Created: 2026-09-06 | Updated: 2026-09-06 | 20 failing / 29 total
• coq(CorePhi): replace proofs that were never checked by a compiler #3343 coq(CorePhi): replace proofs that were never checked by a compiler | Created: 2026-09-06 | Updated: 2026-09-06 | 5 failing / 32 total
• ci(coq): report all thirteen files instead of stopping at the first error #3342 ci(coq): report all thirteen files instead of stopping at the first error | Created: 2026-09-06 | Updated: 2026-09-06 | 3 failing / 30 total
• skill: spool four lessons from this pass #3327 skill: spool four lessons from this pass | Created: 2026-09-05 | Updated: 2026-09-05 | 1 failing / 28 total
• chore(ci)(deps): bump actions/attest-build-provenance from 1 to 4 #3001 chore(ci)(deps): bump actions/attest-build-provenance from 1 to 4 | Created: 2026-09-01 | Updated: 2026-09-06 | 0 failing / 30 total
• chore(ci)(deps): bump softprops/action-gh-release from 2 to 3 #3000 chore(ci)(deps): bump softprops/action-gh-release from 2 to 3 | Created: 2026-09-01 | Updated: 2026-09-06 | 0 failing / 28 total
• chore(ci)(deps): bump github/codeql-action from 3 to 4 #2999 chore(ci)(deps): bump github/codeql-action from 3 to 4 | Created: 2026-09-01 | Updated: 2026-09-06 | 0 failing / 28 total
• Land the formal verification harness on master (it has never run) #2727 Land the formal verification harness on master (it has never run) | Created: 2026-08-27 | Updated: 2026-09-05 | 5 failing / 24 total
• chore(deps)(deps): bump thiserror from 2.0.18 to 2.0.20 #2693 chore(deps)(deps): bump thiserror from 2.0.18 to 2.0.20 | Created: 2026-08-24 | Updated: 2026-08-28 | 3 failing / 34 total
• chore(deps)(deps): bump hyper from 1.10.1 to 1.11.0 #2692 chore(deps)(deps): bump hyper from 1.10.1 to 1.11.0 | Created: 2026-08-24 | Updated: 2026-08-28 | 3 failing / 33 total
• chore(deps)(deps): bump base64 from 0.22.1 to 0.23.1 #2691 chore(deps)(deps): bump base64 from 0.22.1 to 0.23.1 | Created: 2026-08-24 | Updated: 2026-08-28 | 3 failing / 34 total
• chore(deps)(deps): bump serde from 1.0.228 to 1.0.229 #2690 chore(deps)(deps): bump serde from 1.0.228 to 1.0.229 | Created: 2026-08-24 | Updated: 2026-08-28 | 3 failing / 34 total
• chore(deps)(deps): bump uuid from 1.23.2 to 1.25.0 #2689 chore(deps)(deps): bump uuid from 1.23.2 to 1.25.0 | Created: 2026-08-24 | Updated: 2026-08-28 | 3 failing / 34 total
• Unbreak FPGA CI and correct two unbacked hardware claims #2081 Unbreak FPGA CI and correct two unbacked hardware claims | Created: 2026-08-11 | Updated: 2026-08-20 | 5 failing / 27 total

Summary

Status	Count
Total Open PRs	14
PRs with Failing Checks	10
PRs with All Checks Green	4
READY	3
FAILING	10
PENDING	0
NO CHECKS YET	0

These columns do not partition: 3 + 10 + 0 + 0 = 13, and there are 14 open PRs. A PR is being counted twice or not at all.

Seal Status

• ⚠️ STALE -- sha256(compiler.rs)=f503cc3e8477 != manifest seal=87e5cbd3ad94.
  The committed NMSE numbers were certified against an older compiler.rs.
  Run scripts/reseal-check.sh locally for the two-step reseal command (advisory; not a merge gate).