iter pd.3: prelude.ail.json retired — milestone prelude-decouple closed

Deleted examples/prelude.ail.json (-559 lines). The cross-form-identity
preflight test that ratified pd.3's load-bearing assumption at module
hash 3abe0d3fa3c11c99 has discharged its purpose and was removed
along with its supporting bytes; the long-term prelude_parse_yields_canonical_hash
anchor stays. The ail-CLI migrate-bare-cross-module-refs subcommand's
defensive include + lockstep skip-branch removed; the rewrite logic's
prelude-fallback capability silently retired with the synthetic insert
(known debt, doc-comment updated to reflect). One in-mod core test
relocated to crates/ailang-core/tests/workspace_pin.rs (pd.2.4 dev-dep
cycle precedent — in-mod call to ailang_surface still structurally
impossible).

carve_out_inventory.rs: 8 → 7 carve-outs, §C4(b) row dropped, header
sentence updated. form-a-default-authoring.md §C4(b) gets a "RETIRED
2026-05-14 by milestone prelude-decouple" status marker; original
historical text preserved. New prelude_decouple_carve_out_pin.rs
asserts examples/prelude.ail.json does NOT exist.

Milestone prelude-decouple closed: prelude exists on disk only as
examples/prelude.ail; ailang-core embeds zero prelude bytes; CLAUDE.md
"authors write .ail" doctrine holds without exception.

cargo test --workspace 573 green; bench/cross_lang.py +
bench/compile_check.py exit 0; bench/check.py exit 1 with the
established noise envelope (14th observation of bench_list_sum.bump_s
since audit-cma; pd.3 is filesystem + spec text + test deletion only,
no codegen / runtime / typecheck path edited — baseline pristine).

Folds in the orphan pd.2 INDEX entry that was left uncommitted in the
working tree.

crates/ailang-surface/tests/prelude_decouple_carve_out_pin.rs

@@ -0,0 +1,29 @@
+//! pd.3 (`prelude-decouple` milestone): pin that
+//! `examples/prelude.ail.json` does NOT exist on disk. Surfaces
+//! immediately if the file is recreated by accident or a future
+//! refactor reverts the embed-source swap.
+//!
+//! Companion to the `examples_ail_json_inventory_matches_carve_outs`
+//! test in `crates/ailang-core/tests/carve_out_inventory.rs`: that
+//! one asserts the carve-out list is exactly seven; this one
+//! asserts the eighth (retired) file specifically does not exist.
+//! Either test detects an accidental re-introduction; this one
+//! pinpoints the file by name in the error message.
+
+use std::path::Path;
+
+#[test]
+fn prelude_ail_json_does_not_exist_on_disk() {
+    let path = Path::new("../../examples/prelude.ail.json");
+    assert!(
+        !path.exists(),
+        "examples/prelude.ail.json must NOT exist after the prelude-\
+         decouple milestone (closed 2026-05-14). The prelude is now \
+         embedded as prelude.ail in ailang-surface. If you intentionally \
+         re-introduced this file, you must also: (a) remove this pin, \
+         (b) restore the §C4 (b) entry in carve_out_inventory.rs, \
+         (c) revert the §C4 (b) status marker in \
+         docs/specs/2026-05-13-form-a-default-authoring.md, and \
+         (d) record the rationale in a per-iter journal."
+    );
+}

crates/ailang-surface/tests/prelude_module_hash_pin.rs

@@ -1,46 +1,17 @@
-//! pd.2 (`prelude-decouple` milestone): pin the canonical identity of
-//! the parsed prelude.
+//! pd.2/pd.3 (`prelude-decouple` milestone): pin the canonical
+//! identity of the parsed prelude as a literal hex hash. Updates
+//! intentionally on prelude-content changes (record the why in the
+//! per-iter journal); accidental drift trips immediately.
 //!
-//! Two tests:
-//! 1. `prelude_ail_and_json_parse_to_identical_module` — cross-form-
-//!    identity preflight. Asserts that parsing `examples/prelude.ail`
-//!    via `ailang_surface::parse` produces a `Module` with the same
-//!    `module_hash` as deserialising `examples/prelude.ail.json` via
-//!    `serde_json::from_str`. This is the load-bearing assumption
-//!    that justifies pd.3's deletion of the JSON file. pd.3 drops
-//!    this test along with the JSON.
-//! 2. `prelude_parse_yields_canonical_hash` — long-term anchor.
-//!    Asserts the literal hex hash of the parsed Module. Updates
-//!    intentionally on prelude-content changes (with a JOURNAL entry
-//!    naming why); accidental drift trips immediately.
+//! pd.2 also carried a `prelude_ail_and_json_parse_to_identical_module`
+//! cross-form-identity preflight that compared `parse(prelude.ail)`
+//! against `serde_json::from_str(prelude.ail.json)`. The preflight
+//! discharged its purpose at pd.2 close (PASSED at hash
+//! `3abe0d3fa3c11c99`) and was retired in pd.3 alongside the
+//! `prelude.ail.json` file.
 
 use ailang_core::workspace::module_hash;
-use ailang_surface::{parse_prelude, PRELUDE_AIL};
-
-const PRELUDE_JSON: &str = include_str!("../../../examples/prelude.ail.json");
-
-#[test]
-fn prelude_ail_and_json_parse_to_identical_module() {
-    // Form A path: parse prelude.ail via ailang_surface::parse.
-    let from_ail = parse_prelude();
-
-    // Form B path: deserialise prelude.ail.json via serde_json (the
-    // pre-pd.2 path; matches what `ailang_core::workspace::load_prelude`
-    // did before retirement).
-    let from_json: ailang_core::ast::Module = serde_json::from_str(PRELUDE_JSON)
-        .expect("examples/prelude.ail.json must deserialise");
-
-    let h_ail = module_hash(&from_ail);
-    let h_json = module_hash(&from_json);
-
-    assert_eq!(
-        h_ail, h_json,
-        "cross-form-identity preflight failed:\n  parse(prelude.ail) hash:        {}\n  deserialize(prelude.ail.json) hash: {}\n\
-         The two parse paths produce structurally different `Module` values for the same prelude content. \
-         pd.3 must NOT delete prelude.ail.json until this is investigated.",
-        h_ail, h_json,
-    );
-}
+use ailang_surface::parse_prelude;
 
 #[test]
 fn prelude_parse_yields_canonical_hash() {
@@ -55,6 +26,3 @@ fn prelude_parse_yields_canonical_hash() {
          hex below + record the why in the per-iter journal."
     );
 }
-
-// PRELUDE_AIL re-exported for any future test that wants the raw bytes.
-const _: &str = PRELUDE_AIL;