feat: add 7-day uv package cooldown

[sesmaeili-jw]

Description

Adds a 7-day package cooldown to the project's uv configuration to mitigate supply chain attacks. By excluding packages published within the last 7 days from dependency resolution, this reduces exposure to compromised packages — most supply chain attack windows are under a week (80-90% of known cases). The uv.lock file has been regenerated to reflect this constraint.

Fixes: ST-3474

Changes

• Added [tool.uv] section to pyproject.toml with exclude-newer = "7 days"
• Regenerated uv.lock with the cooldown applied (exclude-newer-span = "P7D")

Testing

• Unit tests added/updated
• Integration tests passed
• Manual checks performed: verified uv lock regenerates successfully with the cooldown config and all existing dependencies satisfy the 7-day constraint

Checklist

• Code follows project style guidelines (linting passes).
• Tests added/updated for changes.
• All tests pass locally.
• Documentation updated (if needed).