chore: remove a third-party type from public API

[Fraser999]

[Claude Code]

Per the ticket, alloy and trevm are out of scope (too entrenched). This PR tackles the roaring leak called out explicitly. sqlx was investigated but pulled back to scope (see below).

Changes

signet-storage-types

• IntegerList::iter() returns impl Iterator<Item = u64> + Clone + '_ instead of roaring::treemap::Iter<'_>. roaring no longer appears in any public signature; it remains an internal dependency only. + Clone is retained so callers that forked the iterator continue to compile.

sqlx - considered, deferred

An earlier draft hid sqlx from signet-cold-sql's public API by introducing an opaque SqlPoolConfig wrapping PoolOptions<sqlx::Any>, an opaque SqlBackendError replacing SqlColdError::Sqlx(sqlx::Error), and demoting SqlColdBackend::new(AnyPool) to pub(crate). That draft is reverted in this PR.

The blocker: a fully opaque SqlPoolConfig only exposes ~5 of PoolOptions' ~15 knobs. Notably absent are after_connect (needed for SQLite PRAGMA tuning - journal_mode=WAL, synchronous=NORMAL, busy_timeout), before_acquire/after_release hooks, test_before_acquire, lazy connection, and pool fairness. Recovering each opaquely is its own design problem (callbacks-as-SQL-strings, etc.) and partial removal is the worst of both worlds - it leaks sqlx types implicitly through reduced configurability while still requiring users to learn a new wrapper API. Either we hide sqlx completely (and re-expose every needed knob through opaque shims) or we don't. This PR chooses don't, for now. sqlx joins the "out of scope" table.

Remaining third-party types in storage public APIs (out of scope for this PR)

Crate	Where	Notes
alloy	signet-storage-types, signet-cold, signet-hot, signet-storage	Pervasive: BlockNumber, B256, Address, Filter, Log, Receipt, TxType, table key/value types. Ticket says out of scope.
trevm (re-exports revm)	signet-storage-types::ExecutedBlock.bundle (BundleState); signet-hot::Bytecodes table value (Bytecode); signet-hot::RevmRead/RevmWrite impl Database/DatabaseRef/TryDatabaseCommit. Ticket says out of scope.
sqlx	signet-cold-sql: SqlColdBackend::new(AnyPool), connect_with(_, PoolOptions<sqlx::Any>), SqlConnector::with_pool_options, SqlColdError::Sqlx(sqlx::Error). All-or-nothing ? see above.
tokio_util::sync::CancellationToken	signet-storage (pub use + StorageBuilder::cancel_token, UnifiedStorage::spawn); signet-cold::ColdStorageTask::{new, spawn}	Could be wrapped behind a small facade.
tokio_stream::wrappers::ReceiverStream	signet-cold::LogStream type alias	Could be replaced with a custom Stream-implementing wrapper.
tokio::sync::{mpsc, oneshot}, tokio::time::Instant	signet-cold::Responder alias; signet-cold::StreamParams.{sender, deadline}	Channel endpoints in public types ? harder to hide cleanly.
bytes::BufMut	signet-storage-types::IntegerList::to_mut_bytes; signet-hot::ValSer::encode_value_to bound	Soft leak via generic bound.
serde::{Serialize, Deserialize}	signet-storage-types::{DbSignetEvent, DbZenithHeader} derives	Standard; soft leak.
auto_impl::auto_impl	signet-hot::HotKv/HotKvRead derive	Macro on public traits; soft leak.
signet_libmdbx	signet-hot-mdbx::{Tx<K>, Cursor, SyncMode, Ro/Rw/RoSync/RwSync, TransactionKind}	Borderline ? published as signet- but is functionally a fork of reth-libmdbx. Treat alongside trevm/alloy.

Verification

• cargo +nightly fmt -- --check
• cargo clippy --workspace --all-targets --all-features -- -D warnings
• cargo clippy --workspace --all-targets --no-default-features -- -D warnings
• RUSTDOCFLAGS="-D warnings" cargo doc --workspace --no-deps
• cargo t -p signet-storage-types

[Fraser999]

• chore: remove a third-party type from public API #59 👈 (View in Graphite)
• main

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