Complete bootstrap milestone

docs/PORTING.md

@@ -8,7 +8,7 @@ split into independently testable milestones.
 ## Milestones
 
 1. **Bootstrap** — NeoForge 1.21.1 build, mod metadata, item registration, and
-   CI. (In progress.)
+   CI. **Complete.**
 2. **Books and linking** — descriptive/linking book data components, lectern-like
    interaction, safe teleportation, and return links.
 3. **Ages** — dimension definitions backed by data packs, deterministic seeds,
@@ -36,3 +36,11 @@ The first functional target is: create a Descriptive Book, bind it to one
 server-managed Age definition, travel to that Age, and use a Linking Book to
 return. This exercises persistence, networking, dimensions, and safety before
 the symbol grammar is introduced.
+
+## Milestone 1 acceptance record
+
+- The project builds on a Java 21 JDK with `./gradlew build`.
+- Mod identity and dependencies are declared in generated NeoForge metadata.
+- Registrations are isolated by registry type and use deferred registration.
+- The Descriptive Book loads with a model, name, tooltip, and creative tab.
+- CI builds every pushed commit and pull request.