feat(sdk)!: drop the #[fai_module] alias — #[chain_module] only

No module outside this workspace was ever published against the
alias (the system has no external users yet), so the pre-rename
name goes away instead of being maintained: one attribute, no
legacy surface. All internal doc references swept; echo example
description moves to the product name. 0.3.0.

Signed-off-by: flemming-it <sf@flemming.it>

crates/chain-module-sdk/src/context.rs

@@ -1,7 +1,7 @@
 //! Invocation context passed to a module on every call.
 //!
 //! Mirrors the WIT `invocation-context` record. The
-//! `#[fai_module]` macro builds this from the WIT-generated value
+//! `#[chain_module]` macro builds this from the WIT-generated value
 //! before handing it to user code.
 
 #[derive(Debug, Clone, PartialEq, Eq)]

crates/chain-module-sdk/src/host.rs

@@ -1,7 +1,7 @@
 //! Host-callback plumbing for `Context::emit` (WIT 1.1 `emit-event`).
 //!
 //! The WIT host imports (`emit-event`) are only reachable from the
-//! `wit_bindgen`-generated glue inside the `#[fai_module]` expansion,
+//! `wit_bindgen`-generated glue inside the `#[chain_module]` expansion,
 //! which lives in the module crate — not here. So the macro installs a
 //! function pointer that reaches the real host import, and
 //! [`Context::emit`](crate::Context::emit) calls it through this hook.
@@ -18,7 +18,7 @@ thread_local! {
     static EMIT_HOOK: Cell<Option<fn(&str, Payload)>> = const { Cell::new(None) };
 }
 
-/// Install the emit hook. Called by the `#[fai_module]` expansion at
+/// Install the emit hook. Called by the `#[chain_module]` expansion at
 /// the start of each invocation. Not part of the stable public API.
 #[doc(hidden)]
 pub fn __set_emit_hook(f: fn(&str, Payload)) {

crates/chain-module-sdk/src/inputs.rs

@@ -19,7 +19,7 @@ pub struct Inputs {
 
 impl Inputs {
     /// Build directly from a list of `(name, payload)` pairs.
-    /// Used by the `#[fai_module]` macro after WIT conversion.
+    /// Used by the `#[chain_module]` macro after WIT conversion.
     #[doc(hidden)]
     pub fn __from_pairs(items: Vec<(String, Payload)>) -> Self {
         Self { items }

crates/chain-module-sdk/src/lib.rs

@@ -36,7 +36,7 @@ pub use inputs::Inputs;
 pub use outputs::Outputs;
 pub use payload::{BytesValue, FileRef, Payload};
 
-pub use chain_module_sdk_macros::{chain_module, fai_module};
+pub use chain_module_sdk_macros::chain_module;
 
 // Emit-hook plumbing used by the `#[chain_module]` expansion (wasm32)
 // so `Context::emit` reaches the WIT `emit-event` host import.
@@ -49,7 +49,6 @@ pub(crate) use host::emit;
 pub mod prelude {
     pub use super::{
         BytesValue, Context, FileRef, Inputs, ModuleError, Outputs, Payload, chain_module,
-        fai_module,
     };
 }
 

crates/chain-module-sdk/src/outputs.rs

@@ -71,7 +71,7 @@ impl Outputs {
     }
 
     /// Consume the builder into the underlying `(name, payload)` list.
-    /// Used by the `#[fai_module]` macro after WIT conversion.
+    /// Used by the `#[chain_module]` macro after WIT conversion.
     #[doc(hidden)]
     pub fn __into_pairs(self) -> Vec<(String, Payload)> {
         self.items

crates/chain-module-sdk/src/payload.rs

@@ -2,7 +2,7 @@
 //!
 //! The shape is fixed by the v1.0 WIT freeze. Field-by-field
 //! conversion to and from the WIT-generated type happens inside
-//! the `#[fai_module]` macro expansion in the user crate.
+//! the `#[chain_module]` macro expansion in the user crate.
 
 use serde::{Deserialize, Serialize};