fix(sql): use signed 64-bit Iceberg snapshot IDs

[Solomon-mithra]

Changes Made

Use Option<i64> for SQL read_iceberg snapshot IDs and both scan-builder configurations, following the signedness decision in #7477. This removes pointer-width dependence and lets absent negative IDs reach Iceberg's snapshot lookup instead of failing unsigned-option parsing. Other unsigned table-function options retain their existing validation.

Add deterministic SQL/Python parity tests for IDs above the 32-bit range and at i64::MAX, negative missing-snapshot diagnostics, and invalid literal rejection. Document the ID type. The general SQL number parser is unchanged, including its existing exact-i64::MIN literal limitation.

Validation on macOS ARM64:

• Before the fix, the new regression selection produced 4 expected failures in negative-ID cases and 7 passes.
• After the fix, the SQL Iceberg, table-function and local Iceberg-read suites passed: 71 passed, 1 skipped.
• Native extension build and cargo check -p daft-sql -p daft-logical-plan --no-default-features passed.
• cargo fmt --all -- --check, pinned Ruff 0.14.10 lint/format on the changed Python file, and git diff --check passed.

The native build used a local -C strip=none workaround for macOS linker output rejection; no build configuration changes are included. No 32-bit, Ray or full-workspace CI run was performed locally.

AI disclosure: Codex generated the implementation and regression tests, reviewed the diff, and ran the baseline and post-fix checks above. A second agent independently reviewed the patch; test results described here are agent-run validation.

Related Issues

Closes #7477.

[greptile-apps]

Confidence Score: 5/5

[High impact] The PR appears safe to merge.

Summary

Changes SQL Iceberg snapshot IDs from usize to i64 in the table-function arguments and both scan-builder configurations.

• Removes dependence on pointer width.
• Lets negative IDs reach Iceberg's snapshot lookup.
• Adds SQL/Python parity tests for wide IDs, missing negative IDs, and invalid literals.
• Documents the signed 64-bit ID type.

No actionable issues were found. Solomon-mithra explicitly deferred the existing exact i64::MIN literal limitation.

_{Reviews (1) · Last reviewed commit: "fix(sql): use signed 64-bit Iceberg snap..." · Reviewed by Greptile}

[srilman]

LGTM, just one thing