Add market badges for each ISO/RTO

[AshutoshVJTI]

Context

Market names appear in many places. A consistent badge would make scanning easier.

Scope

Create or reuse a small badge component for ERCOT, MISO, PJM, CAISO, SPP, NYISO, and ISO-NE.

Acceptance criteria

• Badge is readable in dark mode.
• Badge appears in project cards/tables where useful.
• No layout regression on mobile.

Helpful files

• web/components
• web/lib/markets