fix(cli): align live GoClaw API contracts

[mrgoonie]

Summary

• align CLI list parsers with object-wrapped live API responses for agents, sessions, and built-in tools
• update memory and usage commands to current HTTP contracts
• send tools invoke payload as tool/args and add dry-run/context flags
• fail tools custom commands locally because the server does not implement /v1/tools/custom yet

Validation

• /usr/local/go/bin/go test ./...
• /usr/local/go/bin/go build ./...
• /usr/local/go/bin/go vet ./...
• live read-only checks against goclaw.zuey.me: agents list, sessions list, tools builtin list, tools invoke --dry-run, memory list/search, usage timeseries/breakdown

Related: digitopvn/goclaw#35