reorder build-system and project in pyproject

[minhsueh]

Fix Dependabot fail.

updater | 2026/05/15 23:02:47 ERROR <job_1369807079> Error processing job (Dependabot::DependabotError)
2026/05/15 23:02:47 ERROR <job_1369807079> No supported dependency file present.

From Claude Haiku4.5:

The Real Culprit: Dependabot/GitHub Updated Their Parser
Since May 8-9, 2026, GitHub likely updated their Dependabot dependency grapher to be more strict with:

TOML parsing rules
PEP 621 compliance validation
Python dependency file detection logic
This is a Dependabot service-side change, not something you did.

Fix:
Reordering the pyproject for the parser, aligning with modern PEP compliance validation.