feat: add jupiter-api + jupiter-lend skills

[kevarifin14]

Cherry-pick of #19 with signed commits and resolved conflicts. Original author: @tonyagents

Summary

• Adds jupiter-api skill (Solana DEX aggregator — quotes, swaps, limit orders, DCA)
• Adds jupiter-lend skill (lending/borrowing via Jupiter)
• Reviewed A+ — all API endpoints and CLI commands verified

Closes #19
Supersedes #41

🤖 Generated with Claude Code

[kevarifin14]

Heads-up, Kevin — can't approve your own PR but wanted to note what I found:

jupiter-api is A+ as-is. Clean REST docs, all endpoints real, actionable curl + jq examples, correct jupiter-skills plugin block, cross-refs to moonpay-buy-crypto / moonpay-check-wallet / moonpay-swap-tokens. Verified @jup-ag/* npm packages.

jupiter-lend blocks merge. It lists SDK method signatures (deposit(mint, amount), withdraw(jlMint, amount)) but no executable examples — no imports, no initialization, no workflow an agent can follow end-to-end. As written, agents would have to write their own Node code, which violates the repo's no-code rule. Also, @jup-ag/lend-read is under a Proprietary license — worth flagging for commercial use.

Suggestion: split this into two PRs and ship jupiter-api now. Come back to jupiter-lend once there's either a CLI wrapper or concrete runnable examples.