refactor: extract product identity literals into homeboy-product-identity crate

Moves the ProductIdentity struct and PRODUCT_IDENTITY constant (homeboy's
product name, binary name, config/env/artifact/run-dir prefixes) into a new
zero-dependency path-only crate. It's a pristine leaf (std only, 36 LOC) used
by 9 modules including run_dir, whose 26 references to product_identity blocked
its own extraction in the previous engine-primitives cut.

Extracting product_identity now unblocks a future run_dir/temp/paths
extraction without dragging those literals along prematurely. The 30
PRODUCT_IDENTITY call sites are unchanged — core/mod.rs re-exports the crate as
product_identity.

Not published to crates.io; still ships as the single homeboy binary.
cargo check --lib passes.

Author: chubes4

Cargo.lock

@@ -38,6 +38,7 @@ path = "src/bin/bench-audit-self.rs"
 [dependencies]
 # Internal workspace crates (path-only, not published)
 homeboy-error = { path = "crates/homeboy-error" }
+homeboy-product-identity = { path = "crates/homeboy-product-identity" }
 homeboy-engine-primitives = { path = "crates/homeboy-engine-primitives" }
 homeboy-redaction = { path = "crates/homeboy-redaction" }
 

Cargo.toml

@@ -0,0 +1,14 @@
+[package]
+name = "homeboy-product-identity"
+version = "0.1.0"
+edition = "2021"
+license = "MIT"
+authors = ["Chris Huber <chubes@extrachill.com>"]
+description = "Homeboy-owned product literals (name, binary, config/env/artifact prefixes)"
+repository = "https://github.com/Extra-Chill/homeboy"
+
+[lib]
+name = "homeboy_product_identity"
+path = "src/lib.rs"
+
+[dependencies]

crates/homeboy-product-identity/Cargo.toml

@@ -121,7 +121,9 @@ pub mod preview_ingress;
 #[cfg(test)]
 mod preview_ingress_tests;
 pub mod process;
-pub mod product_identity;
+// product_identity moved to the internal `homeboy-product-identity` crate.
+// Re-exported so `crate::core::product_identity::*` call sites keep working.
+pub use homeboy_product_identity as product_identity;
 pub mod project;
 pub mod proof;
 pub mod publication_artifacts;