Adopt @ferrlabs/ui-react in every product app

[BryanFRD]

Context

The org-wide CLAUDE.md mandates that every product app's visual primitives come from @ferrlabs/ui-react (and @ferrlabs/ui-astro for marketing sites). No local Button, Card, Sidebar, Modal when an equivalent ships upstream.

Today, 0 of 5 product apps consume @ferrlabs/ui-react. Each has its own primitive family:

App	Local family	Files using it
FerrFleet-Cloud (FerrAgents)	AgtCard, AgtChip, AgtChrome, AgtTabHeader	12+
FerrVault-Cloud	VltCard, VltButton, VltChip, Vault.tsx	8+
FerrTrack-Cloud	local primitives	TBD
FerrGrowth-Cloud	local primitives	TBD
FerrLens-Cloud	(Astro SSR — uses ui-astro?)	TBD

Why this matters

• Brand drift: each product diverges from the design tokens
• Bug fix multiplier: a a11y fix or RTL fix has to land N times
• Onboarding cost: every new contributor learns N primitive APIs

Sub-issues to spawn (1 per app)

• FerrLabs/FerrFleet-Cloud — migrate app/ from AgtChrome.* to @ferrlabs/ui-react
• FerrLabs/FerrVault-Cloud — migrate app/ from Vault.* to @ferrlabs/ui-react
• FerrLabs/FerrTrack-Cloud — migrate app/ to @ferrlabs/ui-react
• FerrLabs/FerrGrowth-Cloud — migrate app/ to @ferrlabs/ui-react
• FerrLabs/FerrLens-Cloud — confirm @ferrlabs/ui-astro usage on site/

Each migration is sizeable (~1 sprint per app). Recommend doing them in dependency order: FerrFleet first (fewest screens), then FerrVault, then FerrTrack/FerrGrowth.

Pre-work

• For each missing primitive in the lib, add it upstream first (in FerrLabs/UI), release, then consume.