feat(jpa): implement the JPA relational persistence platform

Implements the Stable and Experimental JPA persistence platform designs
against real PostgreSQL, adapted to this repository's fail-closed 19-leaf
registry.

The design models the platform as 25 Gradle projects. `src/settings.gradle`
throws unless the registry holds exactly 19 leaves, so the plan's modules
become packages inside `:adapter:outbound:persistence-jpa` (starter in
`:app-bootstrap`, testkit in its own source set). The full mapping, the
renames this repository's naming gate required, and every deliberate
substitution are recorded in `docs/jpa/repository-adaptation.md`.

Seven Docker-backed lanes replace the plan's seven JVM test suites. Each
fails closed: a lane that discovers nothing, or a container that cannot
start, is an error rather than a skip.

Three defects the contracts found against a real server:

- `CommitFailureClassifier` treated only SQLSTATE 40003, class 08, and
  transport breaks as completion-unknown. A backend terminated mid-commit
  reports 57P01, and the commit record may already be in the WAL — so a
  possibly-committed transaction could be re-run. 57P01/57P02/57P03 now
  classify as completion-unknown.
- `SchemaTenantMigrationOrchestrator` recorded `MigrateResult`'s target
  version, which is empty for a tenant already current, reporting migrated
  tenants as unmigrated during a partial rollout. It now reads the applied
  version back from the tenant's schema history.
- `JpaStreamExecutor` checked only the declared return type for reactive
  publishers, and `RegisteredPostgreSqlCopyLoader` passed the COPY timeout
  to `SET`, which is parsed before parameter binding.

`JpaModuleBoundaryTest` enforces the plan's module map as package rules;
`verifyCleanArchitectureDependencies` governs edges between leaves and
cannot see these. Its first assertion is that the import is non-empty,
because every rule under it is a `noClasses()` rule and would pass
vacuously on an empty import.

Verified: 128 container tests across all seven lanes, 1183 unit tests,
`:adapter:outbound:persistence-jpa:check`, `:app-bootstrap:check`,
`verifyCleanArchitectureDependencies`, `verifyOneTypePerFile`.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>

docs/adr/ADR-JPA-001-domain-owns-persistence-model.md

@@ -0,0 +1,35 @@
+# ADR-JPA-001 — The domain owns the persistence model
+
+- Status: Accepted
+- Date: 2026-08-11
+- Design: §10.1, §23.3
+
+## Context
+
+A persistence platform can either own the repository abstraction — a `GenericRepository<T, ID>`
+every aggregate inherits — or provide only the pieces domains assemble themselves.
+
+## Decision
+
+The domain owns entities, embeddables, repositories, queries, index requirements, and lock,
+soft-delete, and audit policy. The platform provides no generic CRUD repository and no base
+repository. `JpaRepositoryFragmentSupport` exists, has no `save`, `findById`, `findAll`, or
+`delete`, and is enforced not to acquire them.
+
+## Consequences
+
+A generic base repository has one property that looks like a benefit and is not: every aggregate
+gets the same operations. That means each aggregate is offered operations that may be wrong for it —
+a `delete` on an append-only ledger, a `findAll` on a table that will never be small — and, worse,
+one aggregate's later requirement changes the shared base and therefore changes behaviour for
+aggregates nobody reviewed.
+
+Spring Data already implements CRUD. Re-implementing it adds a layer whose only function is to be
+harder to opt out of.
+
+The cost is a small amount of repetition: each domain declares the repository interface it needs.
+That repetition is the thing that makes each aggregate's persistence surface reviewable.
+
+## Enforcement
+
+`JpaArchitectureRules.noGenericRepository()`; `JpaRepositoryFragmentSupportTest`.