Use KindKeyCredentialBase constant for source kind (#21)

[p0dalirius]

Linked Issue

Closes #21

Note

Maintainability/consistency cleanup, not a behavioral bug — included at the maintainer's explicit request. Output is byte-for-byte unchanged.

Root Cause

The source kind was declared twice: as the KindKeyCredentialBase constant in kinds.go and again as a string literal "KeyCredentialBase" passed to gopengraph.NewOpenGraph in main.go. The constant was never referenced, so it was dead code and the two declarations could drift apart over time.

Fix Description

Pass KindKeyCredentialBase to NewOpenGraph so the source kind has a single authoritative definition. Value is identical to the previous literal, so the generated graph is unchanged.

How Verified

Static: KindKeyCredentialBase == "KeyCredentialBase" (kinds.go:4), so the argument to NewOpenGraph is unchanged at runtime. go build ./... and go vet ./... pass.

Test Coverage

None: no behavioral change to test; the substitution is a compile-time constant equal to the prior literal.

Scope of Change

• Files changed: main.go
• Submodule pointer updated: no
• Behavioral changes outside the bug fix: none