Pricing restored — split by value, properties per tier

v0.5.0 over-corrected by dropping pricing entirely. The three-tier split by value (Free / Consumption / Custom) was right and returns as a new section; what's changed is what the bullets say.

• Bullets are now tier properties, not feature gates. Each tier carries exactly three lines, one per axis — MAINTAIN · SCALE · SECURE — describing how that tier is operated (open source no-lock-in self-hosting → managed metered runtime with pre-approval profiles → sovereign deployment with org-wide underwriting and SLAs). The framing line makes it explicit: every tier runs the same product on the same zero-knowledge foundation; sovereignty is the floor, not the premium.
• Enterprise price is now "Custom" (talk to us) rather than a published band.
• Shipped as delta src/v0/v0.5/v0.5.1/ (template + menu + pricing.css); everything else inherits from v0.5.0's delta. v0.5.0 is unlisted from the switcher (superseded within a day — not a distinct design snapshot); its delta folder remains in the chain, which v0.5.1 layers on.
• Smoke suite: menu parity now expects the Pricing section link.