Bound persistence event replay batches

[He-Pin]

Motivation

AsyncWriteJournal can emit an entire recovery stream without waiting for the recovering actor to process it. A large journal can therefore enqueue an unbounded number of replay messages in the persistent actor mailbox and exhaust the heap.

Modification

• Add configurable, acknowledged replay batching with a default batch size of 1000.
• Let classic and typed persistent actors opt in while retaining the existing ReplayMessages request for compatibility with journal plugins that do not understand batching.
• Preserve replay limits, ordering, sender semantics, replay-filter state, cancellation, and recovery isolation across actor or journal restarts.
• Forward the batching protocol through the persistence plugin proxy.
• Add focused classic, typed, replay-filter, protocol, and remote-proxy regression coverage.
• Document the replay batching behavior and configuration.

Result

Recovery bounds the number of replayed events in flight without truncating recovered history. Existing journal plugins continue to use the legacy replay path unless they support the opt-in batching marker.

Tests

• Focused classic protocol, replay filter, and replay batching tests: 24 passed
• Focused typed replay batching tests: 2 passed
• sbt "persistence / Test / test": 63 passed; LevelDB JNI emitted an Apple ARM64/x86 architecture warning
• sbt "persistence-typed-tests / Test / test": 204 passed
• sbt "persistence-shared / Test / testOnly org.apache.pekko.persistence.journal.leveldb.PersistencePluginProxySpec": 1 passed
• sbt headerCreateAll, sbt +headerCheckAll, sbt checkCodeStyle, sbt docs/paradox, and sbt +mimaReportBinaryIssues: passed; Paradox reported duplicate-anchor warnings
• scalafmt --list --mode diff-ref=origin/main and git diff --check: passed
• sbt sortImports: environment/task failure; the project-scoped key was unavailable and root scalafix raised NoSuchMethodError
• sbt validatePullRequest: ran for 28m26s and failed on this macOS ARM64 host because LevelDB JNI 1.8 contains x86 binaries; unrelated docs tests also failed from a missing pekko.dispatch.UnboundedMailbox class and UDP multicast timeouts on all local interfaces

References

Fixes #3241