Scaffold: Cargo.toml + src/ module structure

[pszymkowiak]

Create the initial Rust project structure:

• Cargo.toml with dependencies (thiserror, memmap2) and dev-dependencies (criterion, rusqlite bundled, tempfile)
• src/lib.rs with public API stubs (Database::open, execute, query)
• src/types.rs with Value enum (Null, Integer, Float, Text, Blob) and ColumnDef
• src/storage/mod.rs, src/sql/mod.rs, src/executor/mod.rs module declarations
• benches/vs_sqlite.rs placeholder
• tests/correctness.rs placeholder

The project must compile with cargo check.

[pszymkowiak]

[w] wshm · Automated triage by AI

I've opened draft PR #10 with a potential fix.

A maintainer needs to review and mark it as ready before it can be merged.

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Auto-fixed automatically by wshm · This is an automated analysis, not a human review.