[S5] Emit static tables and gate checked-in generated source against drift

AGENTS.md

@@ -180,7 +180,10 @@ generated output directories. The first figure (1,500) was a guess before
 the baker existed. The cap exists to prevent unbounded growth, not to freeze
 a constant: raise the declared number in `config.ron` (and the mutation
 fixture that names it) when a real kernel needs room. Exceeding the current
-declared cap without that bump is a FAIL.
+declared cap without that bump is a FAIL. `cargo xtask generate` writes the
+checked-in baker generated module declared by `baker.generated`; the
+`generated source` check re-renders it in memory and compares through
+`text::read_text`.
 
 `cargo xtask ci --profile release --nightly nightly-YYYY-MM-DD` is the
 release-evidence mode: every check must run, a would-be `SKIP` is recorded as
@@ -215,6 +218,7 @@ bounded hosted subset is not the complete release evidence.
 | Version or crate `publish` setting | Release process (`RELEASING.md`): root `Cargo.lock`, changelog heading date, `package.version` and `package.manifest.publish` in `xtask/config.ron`, and GitHub `Lifecycle`. README and crate-doc status already describe published `0.1.0` Active; do not revert them to incubating. Pin unpackaged guide URLs (README, `crates/surfaces/src/lib.rs`, `crates/surfaces/examples/*.rs`) from `main` to the release tag. |
 | New packaged file | `include` in `crates/surfaces/Cargo.toml`, and crate-relative `package.files` in `xtask/config.ron` |
 | New baker packaged file | `include` in `crates/surfaces-bake/Cargo.toml`, and crate-relative `baker.files` in `xtask/config.ron` |
+| Baker generated artifact | path in `baker.generated` (`xtask/config.ron`); rewrite with `cargo xtask generate`. Not a runtime packaged file. |
 | New guard in `xtask` | An `Action` variant and required-handler entry in `xtask/src/config.rs`, dispatch in `xtask/src/checks/mod.rs`, a row in `xtask/config.ron`, and a mutation case in `xtask/tests/mutation.rs` showing it fails |
 | Storage or cost wording | `crates/surfaces/src/lib.rs` crate docs, `crates/surfaces/src/surface.rs` / `evaluate.rs` / `axis/` item docs, `README.md` "Resource accounting and cost" |
 | New or changed axis strategy | `crates/surfaces/src/lib.rs` re-exports and § Contract, `README.md` "Per-axis lookup strategies" table, the sixteen-pairing consumer in `tools/consumer/src/lib.rs`, `docs/v0.1-traceability.md` |

CHANGELOG.md

@@ -4,6 +4,19 @@
 
 ### Added
 
+- Host-side baker Rust emission in `ph-surfaces-bake`: `--emit-rust` writes
+  deterministic static knot arrays, a row-major `values[y][x]` grid,
+  `PAYLOAD_BYTES` for the selected pairing, and `MAX_ERR_LSB` to stdout.
+  `--x-bucketed` / `--y-bucketed` reject a bucket count outside the runtime
+  `1..=65_536` bound so the emitter does not print uncompilable
+  `BucketedAxis` source; `emit_rust_with` returns the same closed
+  `BakeError::InvalidBucketCount`. Packaged baker tests do not
+  `include!` the unpackaged generated fixture.
+  `cargo xtask generate` writes the baker-owned checked-in fixture; the
+  `generated source` check re-renders it in memory and fails with
+  `run cargo xtask generate` when it drifts. The bound is an i32 value LSB
+  of sample deviation, not a device or accuracy claim. This is not a
+  runtime API change.
 - Host-side baker quantization in `ph-surfaces-bake`: fill each declared
   grid node from on-knot samples, apply the caller-stated scale with
   round-to-nearest (exact half-way away from zero; values just below a

Cargo.toml

@@ -31,3 +31,5 @@ syn = { version = "3.0.3", features = ["full", "visit"] }
 time = { version = "0.3.55", features = ["macros", "parsing"] }
 toml = "1.1.4"
 walkdir = "2.5.0"
+# Host gate only. The runtime crate must not name this package.
+ph-surfaces-bake = { path = "crates/surfaces-bake", version = "0.1.0" }

crates/surfaces-bake/README.md

@@ -37,11 +37,18 @@ The public host API is `BakeInput::quantize` → `QuantizedTable`, plus
 ph-surfaces-bake --help
 ph-surfaces-bake --samples points.txt --x-knots 0,10 --y-knots 0,5 --scale 1
 ph-surfaces-bake --samples points.txt --x-uniform 0,10,3 --y-uniform 0,5,3 --scale 1
+ph-surfaces-bake --emit-rust --samples points.txt --x-knots 0,10 --y-knots 0,5 --scale 1
 ```
 
-Rust emission and goldens are later issues. The baker may take reviewed host
-crates for exact residual arithmetic. A declared implementation-line budget
-keeps it from growing without bound.
+`--emit-rust` writes Rust source on stdout. The baker does not own the
+destination path; `cargo xtask generate` places the checked-in copy. The
+emitted `MAX_ERR_LSB` is an i32 value LSB: deviation between the supplied
+samples and the table built from them. It is not a device, accuracy, timing,
+or flash claim. `--emit-golden` is not implemented yet.
+
+The baker may take reviewed host crates for exact residual arithmetic. A
+declared implementation-line budget keeps it from growing without bound. The
+generated fixture under `generated/` is not part of the packaged crate.
 
 ## License
 

crates/surfaces-bake/generated/rounding.rs

@@ -0,0 +1,22 @@
+// @generated by `cargo xtask generate`; do not edit by hand.
+
+use ph_surfaces::BilinearSurface;
+
+static X: [u16; 2] = [0, 2];
+static Y: [u16; 2] = [0, 2];
+#[rustfmt::skip]
+static VALUES: [[i32; 2]; 2] = [
+    [0, 1],
+    [1, 2],
+];
+
+/// Pairing: BinaryAxis × BinaryAxis.
+/// Referenced element payload, not total RAM, flash, binary, or linker cost.
+pub const PAYLOAD_BYTES: usize = 24;
+
+pub static SURFACE: BilinearSurface<2, 2> =
+    BilinearSurface::new(&X, &Y, &VALUES);
+
+// MAX_ERR_LSB is an i32 value LSB: deviation from supplied samples, not
+// device, accuracy, timing, or flash.
+pub const MAX_ERR_LSB: i32 = 1;