[SPIKE] Support Token Discoverability on Search

[ginny-stacks]

Token discoverability is limited, especially for specific token categories such as Stablecoins or Liquid Staking Tokens. Users cannot search by token name, symbol/ticker, or category

Solution: Allow searching by:

• Token name
• Token symbol / ticker
• Token category (e.g., Stablecoins, LSTs)

References Design: https://www.figma.com/design/gsgfw9WmMbETBEC4FbY2H9/Stacks-Explorer--Redesign-?node-id=4198-34003&t=QPDT75kynZZXZYB7-1

Related issues: https://github.com/stx-labs/explorer/issues/2484 https://github.com/stx-labs/explorer/issues/2662