fix: sources breadcrumb dead link

[chase-crumbaugh]

Rather than the sources page "index" being a nonexistent half-page, this makes it show the same thing as the toolsets page

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Latest commit: a2197e7

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Project	Deployment	Review	Updated (UTC)
gram	Ready	Preview, Comment	Jan 7, 2026 1:53am
gram-docs-redirect	Ready	Preview, Comment	Jan 7, 2026 1:53am