revert(spec): take back the declaration-text snapshot, restore the 27 signature hashes

.gitattributes

@@ -144,10 +144,10 @@ packages/spec/authorable-surface.base.json                   merge=os-regen
 packages/spec/authorable-defaults/**                         merge=os-regen
 packages/spec/json-schema.manifest/**                        merge=os-regen
 packages/spec/api-surface/**                                 merge=os-regen
-packages/spec/api-surface-declarations/**                     merge=os-regen
 packages/spec/src/meta-spelling/meta-url-data.generated.ts   merge=os-regen
 packages/spec/export-origins/**                              merge=os-regen
 packages/spec/declaration-map/**                             merge=os-regen
+packages/spec/api-surface-signatures.json                    merge=os-regen
 docs/protocol-upgrade-guide.md                               merge=os-regen
 docs/audits/2026-07-unknown-key-strictness-ledger.counts.md  merge=os-regen
 content/docs/references/**                                   merge=os-regen

.github/workflows/lint.yml

@@ -5173,16 +5173,11 @@ jobs:
 
       # The authorable KEY surface — what a metadata author may write, which for
       # this platform is the third-party API. `api-surface/` records exported
-      # names only, so it does not see a key added to or removed from a schema;
-      # the shape sibling that used to sit beside it (`api-surface-signatures.json`,
-      # retired at #16045) hashed factory types as TypeScript PRINTS them — a
-      # reference, never structurally expanded — so it did not see one either.
-      # #3883 removed three authorable keys with every witness green; #3733 did it
-      # by accident. ADR-0059 §5 deferred this gate until a narrowing actually
-      # slipped both — it has. `check:api-surface-declarations` (consumer-gates
-      # lane) now records the declaration TEXT of every export, which DOES move on
-      # such a key; this gate stays the authority on the AUTHORABLE key set, which
-      # is a different question from the declared TypeScript shape.
+      # names and `api-surface-signatures.json` hashes factory types as TypeScript
+      # PRINTS them (a reference, never structurally expanded), so neither sees a
+      # key added to or removed from a schema. #3883 removed three authorable keys
+      # with every witness green; #3733 did it by accident. ADR-0059 §5 deferred
+      # this gate until a narrowing actually slipped both — it has.
       #
       # ⚠ ORDER: this step must stay ABOVE the `check:docs` step below. Its
       # `--check` run of scripts/build-schemas.ts writes the gitignored
@@ -6104,29 +6099,6 @@ jobs:
       - name: Check @objectstack/spec public API surface
         run: pnpm --filter @objectstack/spec run check:api-surface
 
-      # [#16045] The SHAPE half of the same surface, and the step the card above
-      # exists for: `api-surface/` pins 5336 `name (kind)` rows and a signature
-      # change, a renamed interface field and a dropped union member move NONE of
-      # them, so 99.5% of the pinned surface could not go red on a breaking shape
-      # change to a ratified public type. The declaration-text snapshot records
-      # what the packed `.d.ts` actually declares for every export, per entry
-      # point. Ruled at #16045 (director batch #60, maintainer 「同意」): text and
-      # ⛔ NOT a hash, because a red hash gets accepted rather than investigated
-      # and a readable diff is what makes contract review a guard.
-      #
-      # WHY THIS LANE. It resolves each entry point through the `exports` map to
-      # the BUILT `.d.ts` — the declarations a consumer installs — so it is
-      # build-dependent and sits after the two build steps above with its family
-      # (`check:api-surface`, `check:published-readme-exports`). A missing or
-      # stale dist is a HARD REFUSAL in both of the script's modes, never a skip:
-      # a build-dependent gate that silently reads nothing reports "not measured"
-      # as if it were "measured and clean" (#4690).
-      #
-      # It adds no required context: a step in an existing lane, so no open PR
-      # waits on a check whose name no head has ever reported (#9325).
-      - name: Check @objectstack/spec declaration text (the shape half)
-        run: pnpm --filter @objectstack/spec run check:api-surface-declarations
-
       # [#11350] Consumer-shaped declaration-emit pin against the BUILT root
       # entry (an un-annotated `export default defineStack(...)` must compile
       # with `declaration: true` — the TS2883 class). The pin is environment-

docs/spec-generated-artifact-sharding.md

@@ -41,12 +41,7 @@ arithmetic composes on a merge and the judgement does not).
 
 - **`spec-changes.json`** — keyed by version, so two PRs append under different majors.
   Never a conflict surface worth splitting.
-- **`api-surface-signatures.json`** — RETIRED at #16045, and the one row here whose reason
-  did not survive its own artifact. It was 1.3KB, one line per `defineX` factory, so it was
-  never worth splitting. Its replacement is the opposite shape: `api-surface-declarations/`
-  holds the declaration TEXT of every export (12 MiB across 17 shards on the tree that
-  landed it), so it is sharded per entry point from the day it arrived, for the same
-  merge-queue reason `api-surface/` is.
+- **`api-surface-signatures.json`** — 1.3KB, one line per `defineX` factory.
 - **`authorable-surface.base.json`** — the #5235 deletion-gate anchor. Nothing but an
   explicit `gen:authorable-surface-base` writes it (#5358), so it was never on the churn
   path that made the other three the queue's serialization point. It also carries **one**