fix(deparser): emit EXCLUDE clause in window frame specifications

[gwinchesters]

Summary

Fixes #282

formatWindowFrame in the deparser was silently dropping EXCLUDE CURRENT ROW, EXCLUDE GROUP, and EXCLUDE TIES when deparsing window frame specifications.

Root cause: Hardcoded exact-match comparisons on frameOptions (e.g. === 789, === 1077) failed when any EXCLUDE bit was set, since the EXCLUDE bits change the integer value. Additionally, the function never checked for or emitted the EXCLUDE bits.

Fix:

• Mask out EXCLUDE bits (0x8000, 0x10000, 0x20000) before exact-match comparisons
• Append the appropriate EXCLUDE clause after building the frame bounds

Test plan

• Added 3 window fixture tests covering EXCLUDE CURRENT ROW, EXCLUDE GROUP, and EXCLUDE TIES
• All 132 window fixture tests pass (round-trip AST comparison)

First-time contributor here — happy to adjust anything if this doesn't follow the project's conventions.

[mgagliardo91]

Thanks @gwinchesters for the implementation 🙏 .

@pyramation any chance you could take a look at this PR? We are having to use a patched version to support this for now and would appreciate being able to remain on the standard release versioning.