release(java): 7.20.12 — #233 maven parallel-build deadlock fix (Maven-only)

Maven Central only (npm/PyPI/NuGet stay at 0.20.11 — the fix is Java-only).
Bumps the 13 publishable modules 7.20.11 -> 7.20.12. Ships #233: RegistryBootstrap
warm-up + per-instance activeLoaders key + threadSafe generate/verify/docs.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01HLoJkFSyoticveo5ehMUAr

Author: dmealing

CHANGELOG.md

@@ -5,6 +5,16 @@ here. The format follows [Keep a Changelog](https://keepachangelog.com/), and
 this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.html)
 (pre-1.0; MINOR bumps may introduce breaking changes with notice).
 
+## [7.20.12] — 2026-08-02
+
+**Maven-only PATCH** — Maven Central `7.20.12` (npm/PyPI/NuGet unchanged at `0.20.11`; the fix is Java-only, so only the Maven line moves — Maven now runs one patch ahead of the shared `20.11`, mirroring how npm runs a patch ahead with npm-only fixes). Fixes **[#233](https://github.com/metaobjectsdev/metaobjects/issues/233)**: a multi-module Maven reactor building `metaobjects-maven-plugin` in **parallel** (`mvn -T<N>`) deadlocked/hung; the serial default (`-T1`) always worked. Two compounding causes, both fixed:
+
+- **Deadlock (Part A).** On the first load, several **independently-locked process-global registry singletons** — `RegistryManifest.defaultLoaderRegistry()` (DEFAULT_LOCK), `MetaDataRegistry.getInstance()` (INSTANCE_LOCK, reached via `ConstraintEnforcer.getInstance()` on the first `addChild`), and `ServiceRegistryFactory.getDefault()`, plus the JVM class-init locks of the ~18 type providers — could be acquired by two loader threads in **different orders** (a classic lock-ordering deadlock). `MavenLoaderConfiguration` first-touches the sealed registry on the Maven worker thread with no timeout, so a deadlock there wedged the reactor forever. A new **`RegistryBootstrap.warmUpDefaults()`** deterministically initializes those singletons on a single thread under one lock **before** any parallel first-init can race them; it is called from `MetaDataLoader.initWithConcurrencyProtection` (covers every loader embedder — Spring, parallel test runners, servers — not just Maven) and the mojo `execute()`s (covers Maven's pre-`init()` eager registry touch).
+- **Cross-module loader sharing (Part B).** The load runs on `ForkJoinPool.commonPool()` via a static `activeLoaders` map keyed `class:subType:name` (no instance identity), so two reactor modules configuring a `<loader>` with the **same name** shared one init future — module B's `init()` returned module A's loader and left B's own tree UNINITIALIZED (silent wrong output, or the build failing with `MetaDataLoader [name] is not usable`). `MetaDataLoader.buildLoaderKey()` now includes a process-unique instance id, so the dedup only coalesces concurrent `init()` on the **same** instance.
+- The `generate` / `verify` / `docs` mojos are now declared `@Mojo(threadSafe = true)` — honest labeling that ships atomically with the fix (Maven 3.x does not serialize non-threadSafe mojos under `-T`, it only warns); `editor` (direct-invocation) and `agent-docs` (stub) intentionally remain unmarked.
+
+Existing single-module `meta:gen` output is **byte-identical** (the warm-up only front-loads existing lazy init; the per-instance key changes only the dedup key). Verified with a 3-module `-T4` reactor before/after (unfixed: 8/8 runs fail on the shared-name module with `Phase: UNINITIALIZED`; fixed: 5/5 pass with per-module isolation) plus new unit tests (`LoaderKeyIsolationTest`, `RegistryBootstrapTest`, `MojoThreadSafeDescriptorTest`) and the full `metadata` + `maven-plugin` + `codegen-spring` + `codegen-kotlin` suites. Maven-only change (Java maven-plugin + metadata registry); no TS/Python/C# product changes. See `docs/superpowers/specs/2026-08-02-issue-233-maven-parallel-build-deadlock-design.md`.
+
 ## [0.20.11] — 2026-08-02
 
 **Coordinated PATCH** — npm `0.20.11` · PyPI `0.20.11` · NuGet `0.20.11` · Maven Central `7.20.11`.

CLAUDE.md

@@ -6,7 +6,7 @@
     <parent>
         <groupId>com.metaobjects</groupId>
         <artifactId>metaobjects</artifactId>
-        <version>7.20.11</version>
+        <version>7.20.12</version>
     </parent>
 
     <artifactId>metaobjects-codegen-base</artifactId>

server/java/codegen-base/pom.xml

@@ -7,7 +7,7 @@
   <parent>
     <groupId>com.metaobjects</groupId>
     <artifactId>metaobjects</artifactId>
-    <version>7.20.11</version>
+    <version>7.20.12</version>
   </parent>
 
   <artifactId>metaobjects-codegen-kotlin</artifactId>

server/java/codegen-kotlin/pom.xml

@@ -6,7 +6,7 @@
     <parent>
         <groupId>com.metaobjects</groupId>
         <artifactId>metaobjects</artifactId>
-        <version>7.20.11</version>
+        <version>7.20.12</version>
     </parent>
 
     <artifactId>metaobjects-codegen-mustache</artifactId>

server/java/codegen-mustache/pom.xml

@@ -6,7 +6,7 @@
     <parent>
         <groupId>com.metaobjects</groupId>
         <artifactId>metaobjects</artifactId>
-        <version>7.20.11</version>
+        <version>7.20.12</version>
     </parent>
 
     <artifactId>metaobjects-codegen-plantuml</artifactId>

server/java/codegen-plantuml/pom.xml

@@ -6,7 +6,7 @@
     <parent>
         <groupId>com.metaobjects</groupId>
         <artifactId>metaobjects</artifactId>
-        <version>7.20.11</version>
+        <version>7.20.12</version>
     </parent>
 
     <artifactId>metaobjects-codegen-spring</artifactId>

server/java/codegen-spring/pom.xml

@@ -6,7 +6,7 @@
     <parent>
         <groupId>com.metaobjects</groupId>
         <artifactId>metaobjects</artifactId>
-        <version>7.20.11</version>
+        <version>7.20.12</version>
     </parent>
 
     <artifactId>metaobjects-core-spring</artifactId>

server/java/core-spring/pom.xml

@@ -7,7 +7,7 @@
   <parent>
     <groupId>com.metaobjects</groupId>
     <artifactId>metaobjects</artifactId>
-    <version>7.20.11</version>
+    <version>7.20.12</version>
   </parent>
 
   <artifactId>metaobjects-integration-tests-kotlin</artifactId>

server/java/integration-tests-kotlin/pom.xml

@@ -7,7 +7,7 @@
   <parent>
     <groupId>com.metaobjects</groupId>
     <artifactId>metaobjects</artifactId>
-    <version>7.20.11</version>
+    <version>7.20.12</version>
   </parent>
 
   <artifactId>metaobjects-integration-tests</artifactId>