fix: Apply SQLite optimizations to the custom connection_string in SqlStorageClient

[Mantisus]

Description

• Since crawlee can have highly concurrent access to the database, SQLite optimizations must be applied, the most critical being journal_mode=WAL. If a user wants fine-grained control over connections, they should pass a custom engine instead of a 'connection_string'.

Issues

• Relates: SqlStorageClient silently swallows write errors, causing data loss #1831

[Copilot]

Pull request overview

Applies SQLite concurrency/performance pragmas (notably journal_mode=WAL) even when SqlStorageClient is configured via a custom SQLite connection_string, rather than only for the default database path.

Changes:

• Replace the “default DB only” gate with a SQLite-specific optimization gate based on the provided connection_string.
• Ensure SQLite pragmas are executed during initialization for SQLite connection strings when engine is not explicitly provided.
• Update uv.lock metadata/options for dependency resolution reproducibility.

Reviewed changes

Copilot reviewed 1 out of 2 changed files in this pull request and generated 1 comment.

File	Description
uv.lock	Adds uv lock options (exclude-newer, span) affecting how the lock was produced/resolved.
src/crawlee/storage_clients/_sql/_storage_client.py	Expands SQLite pragma application to custom SQLite connection_string configurations (when engine is not provided).

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[vdusek]

LGTM, @Mantisus can I merge it? 🙂

[janbuchar]

Could we instead set up an _on_connect callback here that would receive the new DB connection? That way, the logic (if sqlite, set up some pragmas) would be in one place.