build(deps): Update gluesql-core requirement from 0.15 to 0.18

[dependabot]

Updates the requirements on gluesql-core to permit the latest version.

Release notes

Sourced from gluesql-core's releases.

v0.18.0 🌈

🌊 Breaking Changes

• Storage traits are now Send + Sync – custom storages must switch from Rc/RefCell to thread-safe primitives to satisfy the new bounds introduced in #1688. This lets GlueSQL operate cleanly in multi-threaded runtimes.
• Value::evaluate_eq returns a tri-state result – equality checks now produce a new Tribool type so NULL comparisons behave per SQL rules (#1705). If you called this helper directly, update call sites to handle True/False/Null.
• Statement::to_sql() removed – GlueSQL's AST is no longer serialised back to SQL strings. Consumers that relied on the method should build SQL using sqlparser-rs instead (#1746).
• Minimum supported Rust version: 1.89 – the workspace toolchain moved to Rust 1.89 (#1747, #1762). Update local toolchains and CI images before upgrading.

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✨ Highlights

Derive structs from query results (no manual row mapping!)

• The new FromGlueRow derive macro and rows_as/one_as helpers turn SELECT payloads into your own structs with zero boilerplate (#1779). The derive ships directly from the crate root, so any application can opt into typed results with a single attribute:

#[derive(gluesql::FromGlueRow)]
struct User {
    id: i64,
    name: String,
}
let users = glue
.execute("SELECT id, name FROM users;")
.await?
.rows_as::<User>()?;
let first = glue
.execute("SELECT id, name FROM users WHERE id = 1;")
.await?
.one_as::<User>()?;

• Result conversion works on individual Payloads or the entire execute result, and documentation/examples now showcase the pattern for immediate adoption.
• The derive now maps UUID values into String fields without extra helpers and qualifies its generated Result usage so local aliases continue to compile (#1796, #1797); the README and hello world example were refreshed to match (#1790).

Full SELECT DISTINCT support

• GlueSQL now recognises DISTINCT in projections and across aggregate functions, including COUNT(DISTINCT *), SUM(DISTINCT col) and friends (#1710). AST Builder gained .distinct() helpers and the executor deduplicates rows during planning.

New SQL functions

• Date & time: CURRENT_DATE, CURRENT_TIME, CURRENT_TIMESTAMP (also callable with parentheses) (#1677).
• Conditional: NULLIF (#1683).
• Numeric/string: HEX (#1694) and TRUNC (#1787).

Improved NULL semantics & grouping

• Expression evaluation now short-circuits to NULL when any operand is NULL (#1685), and equality checks propagate tri-state truth (#1705).
• Aggregate keys use full Value instances instead of Key, enabling GROUP BY on MAP and LIST columns (#1768).
• Value, Point and related structures implement consistent PartialEq, Eq, and Hash, improving plan caching and set semantics (#1724, #1729).

Storage updates

... (truncated)

Commits

• 6631a97 Fix macros dev dependency cycle (#1798)
• 723b064 Release v0.18.0 (#1791)
• 790b1aa Qualify Result usage in FromGlueRow derive (#1797)
• 507fa40 Update docs to demonstrate FromGlueRow (#1790)
• 7c199cf Support UUID-to-String in FromGlueRow (#1796)
• 7960be6 Update AGENTS.md to document grouped use convention (#1788)
• bbb8f5d Implement proc macro for row conversion and add payload helpers (minimal SELE...
• e0342cc Add TRUNC function support (#1787)
• 0361411 Update existing PR coverage comment instead of creating new one (#1784)
• 06921f9 Update web storage dependencies (#1783)
• Additional commits viewable in compare view

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