Add SQLite compiletime natives

[Donach]

Summary

Add SQLite-backed compiletime natives to the interpreter:

• open and close database connections
• prepare, bind, step, reset, and finalize statements
• read integer, real, and string result columns
• execute direct SQL statements

The API uses integer handles at the Wurst boundary while keeping JDBC resources encapsulated in CompiletimeNatives. Bind indexes follow JDBC's 1-based convention; result column indexes are 0-based for Wurst array-style access.

Motivation

Wurst projects with larger structured content catalogs currently have to generate or parse intermediate text before compilation. Compiletime SQLite access lets them query a reviewed SQLite catalog directly while object generation and compiletime registration run.

The compiler already ships sqlite-jdbc; this change exposes that existing capability to compiletime Wurst code without adding a dependency.

Resource and error handling

• statements are tracked against their owning connection
• closing a connection finalizes its remaining statements
• reset closes the active result set while retaining the prepared statement
• invalid handles produce explicit interpreter errors
• JDBC cleanup failures are reported rather than silently ignored
• direct execution uses try-with-resources

Tests

The interpreter-level test exercises an in-memory database end to end, including:

• schema creation and direct execution
• prepared statements
• integer and string binding
• stepping and column access
• reset, finalization, and connection close

Validation run against upstream 50080cdb9f4e8dda9361feb40a42f7bdfb8f6f21:

• ./gradlew test --tests tests.wurstscript.tests.CompiletimeTests.testCompiletimeSQLite
• ./gradlew test --tests tests.wurstscript.tests.CompiletimeTests --tests tests.wurstscript.tests.CompiletimeNativesTest
• ./gradlew shadowJar --no-daemon
• ./gradlew test --no-daemon — full suite passed