DarshJDB v0.3.3 — Executor Rewire + SqliteStore::query + mlua ddb.kv.*

[0.3.3] - 2026-04-15 — Executor Rewire + SqliteStore::query + mlua ddb.kv

Sprint internally referred to as "v0.3.2.1" in agent SUMMARY files
and DEFERRED.md. Released as v0.3.3 because Cargo workspace versions
are strict three-part semver — the post-release "0.3.2.1" naming is
not a valid cargo version field. No semantic difference; this is
the patch release immediately following v0.3.2.

Closes the two integration deferrals from the v0.3.2 sprint so the
SQLite backend has a real read path and the DarshanQL executor knows
which dialects can run which statement types.

Added

• SqliteStore::query real implementation — the v0.3.2 stub that
  returned InvalidQuery for every plan is gone. SqliteStore::query
  now binds serde_json::Value params through a small ToSql adapter,
  expands the v0.3.2 M-3 __UUID_LIST__ token into per-uuid ?N
  placeholders for nested-plan resolution, executes via rusqlite on a
  blocking task, and materialises rows in the same QueryResultRow
  JSON shape PgStore::query returns so downstream consumers see no
  shape drift across backends. Plans carrying the
  __SQLITE_VECTOR_UNSUPPORTED__ /
  __SQLITE_COSINE_DISTANCE_UNSUPPORTED__ sentinels are refused up
  front with a clear InvalidQuery message.
• SqlDialect capability gates — three new methods
  (supports_ddl, supports_graph_traversal, supports_hybrid_search)
  with default-true so PgDialect inherits the v0.3.1 surface
  unchanged. SqliteDialect overrides all three to false. The
  DarshanQL executor checks them at dispatch time.
• darshql::ExecutorContext — a {pool, Arc<dyn Store>, Arc<dyn SqlDialect>} bundle threaded through every executor
  function. The HTTP entry point keeps the existing
  execute(&PgPool, …) signature for backwards compatibility and
  constructs the context internally; new call sites (tests, future
  portable runners) use execute_with_context directly.
• tests/sqlite_e2e_query.rs — six end-to-end integration tests
  covering bare SELECT, $where Eq, $where Neq, $limit + $offset,
  $order ASC, and the empty-result case against an in-memory
  SqliteStore driven through plan_query_with_dialect + the new
  Store::query path. Plus two matching store::sqlite::tests
  unit tests and three new query::dialect::tests capability checks.

Added — mlua ddb.kv.* host API

• MluaContext.cache: Arc<DdbCache> — the v0.3.2 stub fields
  for ddb.kv.get/set/del are gone. MluaContext now carries the
  cache handle alongside the store + dialect, and main.rs wires
  it from a single shared_ddb_cache: Arc<DdbCache> constructed
  before AppState::with_pool so REST/RESP3 dispatchers and the
  Lua function runtime hold the same Arc — Lua writes from a
  server function are immediately visible to subsequent REST
  cache GETs and vice versa.
• ddb.kv.get(key) — returns a Lua string for UTF-8 values,
  nil for missing keys, and raises a Lua RuntimeError if a
  present value is not valid UTF-8 (binary blobs belong in object
  storage, not the string-shaped Lua boundary).
• ddb.kv.set(key, value [, ttl_seconds]) — accepts an
  optional trailing Option<u64> TTL. 0 is treated as
  "no expiry" so dynamic-TTL callers don't need to special-case
  the zero literal.
• ddb.kv.del(key) — returns a bool indicating whether the
  key existed across any cache tier prior to deletion.
• 5 new mlua tests exercising roundtrip, TTL expiry, deletion,
  missing-key, and the non-UTF-8 error path. The total mlua test
  count is now 30 passing (up from 23 in v0.3.2).
• Stub-error assertion trimmed — the v0.3.2 mlua hardening
  sprint added a ddb_stubs_all_raise_lua_error test that loop-
  asserted ddb.kv.* raised NotYetImplemented. That assertion
  is now wrong; the kv methods are removed from the loop and the
  test continues to guard the still-stubbed ddb.notify and
  friends (if any).

Changed

• DarshanQL executor — Tier 2 statement-type gates. DEFINE TABLE, DEFINE FIELD, RELATE, SELECT fields containing
  ->edge traversal, and count(->edge) computed fields now check
  ctx.dialect.supports_*() and return InvalidQuery with a
  v0.3.3-tracking message on dialects that don't support them
  (SQLite today). PostgreSQL production behaviour is byte-for-byte
  unchanged because PgDialect inherits the default-true.
• Workspace version bumped 0.3.2 → 0.3.3 (released as v0.3.3
  because Cargo's strict three-part semver disallows a 0.3.2.1
  version field; sprint files and agent reports retain the
  v0.3.2.1 naming for traceability).

Deferred to v0.3.2.2 / v0.3.3

• The portable Pg-or-SQLite hookup for SELECT / CREATE / INSERT /
  RETRACT through ctx.store (rather than ctx.pool) is plumbed
  through ExecutorContext but the executor body still reaches for
  the pool directly for the read/write SQL — the SurrealQL-shaped AST
  consumed by query/darshql/executor.rs is independent of the
  JSON-shaped QueryAST driven by plan_query_with_dialect, and the
  v0.3.3 milestone tracks unifying the two planner surfaces so the
  same Store::query path serves both. Until then the gates are the
  safety net.
• INFO FOR against :schema/* triples on SQLite — the storage
  shape is portable but the planner pieces have not been ported.
  Tracked alongside the DDL gate in v0.3.3.
• See DEFERRED.md for the full deferral list with rationale.

Full Changelog: v0.3.2...v0.3.3