[Feature] Additional persistence backends: MongoDB, DynamoDB, MSSQL, libSQL/Turso, Cloudflare D1 (umbrella)

[pathosDev]

Umbrella issue — one checkbox per backend; each backend lands as its own PR against this issue.

Rationale

Persistence currently ships in-memory, SQLite, Cassandra/ScyllaDB, PostgreSQL and MariaDB. Common stacks are missing; and the edge-oriented backends (libSQL/Turso, Cloudflare D1) directly enable the WASM/edge runtime ambition (#209).

Scope (checkboxes)

• MongoDB (journal + snapshot store + durable state)
• DynamoDB (journal + snapshot store + durable state)
• MS SQL Server (journal + snapshot store + durable state)
• libSQL / Turso (SQLite dialect over HTTP)
• Cloudflare D1 (SQLite dialect over HTTP API)

Per backend: the full trio following the Postgres/MariaDB plugin pattern (schema bootstrap, optimistic concurrency, tagging where the store supports it — document a tagging-support matrix), integration test via container/emulator, docs page EN + DE.

Dependency policy (binding): drivers are optional lazy peerDependencies only. libSQL/Turso and D1 should be implemented SDK-free over their HTTP APIs via the built-in HttpClient where practical.

Documentation

Persistence docs: backend matrix update + one page per backend (EN + DE); CHANGELOG per backend.

Acceptance (per backend)

• Journal/snapshot/durable-state contract test suite green against the real store (containerized); recovery + tagging behavior verified; no new hard dependency.

Relates

#71 (bulk wrap-legacy migration), #209 (edge runtimes), #377–#383 (persistence robustness — land first). Dependency policy #419. Improvement program M8.

[pathosDev]

All five backends shipped — the issue's own 5/5 checkboxes, verified against source.

Backend	Trio	Notes
MongoDB (#397)	journal + snapshot + durable-state + MongoQuery	First indexed tag query outside SQL/Cassandra (multikey index over tags); needs no transactions, so it runs on a standalone mongod
DynamoDB (#398)	full trio	Strongest concurrency of any backend — one TransactWriteItems with attribute_not_exists per put, atomic across items, so no partial-append caveat
MS SQL (#399)	full trio	Four genuine T-SQL dialect additions; verified to import and build a pool on Bun, Node and Deno 2
libSQL / Turso (#400)	full trio	Closed separately as #400
Cloudflare D1	full trio	Over D1's REST API with the framework's own HttpClient — no dependency at all

Every driver is an optional lazy peer per peerDependenciesMeta. Tagging-capability matrix documented at docs/…/persistence/overview.mdx:68, EN + DE docs per backend, and live integration suites for Mongo / Dynamo / MsSql / LibSql.

Two limits recorded rather than papered over: D1 is verified against a FakeD1Client because no local emulator fits a container suite (it exists only inside wrangler/Miniflare), and its withTransaction provides no isolation since the HTTP API has no BEGIN — which SqlPool always specified as adapter-defined.

Follow-ons split out rather than left implicit: #490 (CassandraDurableStateStore via LWT) and #491 (collapse SqliteJournal onto RelationalJournal).