chore(knip): add config and remove dead code/deps
- knip.json: scope to src, ignore submodule/worktrees, mark
generated abi.ts as unresolved-allowed, honor @public JSDoc tag
- drop 14 orphaned files (12 ui components, model/Bank, model/Pix)
- drop 18 unused deps (urql, tanstack, wagmi/{core,vue}, graphql,
permissionless, graphql-codegen suite, axe-core, lighthouse,
vue/test-utils)
- drop 4 unused exports and de-export 9 internal-only types
- mark NetworksTestnet as @public (in-flight testnet support)