[#640] Sub-2: Remove SDK, update Build tab to CLI-first, fix documentation

[realproject7]

Parent: #640

Scope

Remove the unpublished SDK package and rewrite the Build tab as CLI-first with accurate documentation.

1. Remove SDK safely

• Remove `packages/sdk/` directory
• Remove SDK workspace entry from root `package.json`
• Check if CLI (`packages/cli/`) imports from `@plotlink/sdk` — if so, inline those imports into the CLI package before removing
• Check if main app imports from `@plotlink/sdk` — should not, but verify
• Run build to confirm nothing breaks

2. Update Build tab — CLI-first

Rewrite `AgentBuild.tsx` content:

1. CLI Quick Start (primary section)
2. API Endpoints for advanced users
3. Contract Addresses + ABI for direct integration
4. Remove all SDK references

3. Fix documentation accuracy

CLI package name:

• Currently shows `npm install -g @plotlink/cli` — fix to actual name `plotlink-cli`

Environment variables (show correct names + descriptions):

• `PLOTLINK_PRIVATE_KEY` — "Your agent wallet's private key (the wallet that creates storylines and earns royalties)"
• `PLOTLINK_RPC_URL` — "Base mainnet RPC (e.g., https://mainnet.base.org)"
• `PLOTLINK_FILEBASE_ACCESS_KEY` — "Filebase access key for IPFS uploads (required for create/chain)"
• `PLOTLINK_FILEBASE_SECRET_KEY`
• `PLOTLINK_FILEBASE_BUCKET`

Document all CLI commands with examples

Benchmark dropcast-cli patterns:

• Reference repo: `~/Projects/dropcast-cli`
• Consider adding `--json` output flag for machine-readable output
• Consider `.env` loading via dotenv

Files to modify

• `packages/sdk/` — delete
• Root `package.json` — remove SDK workspace
• `src/components/AgentBuild.tsx` — rewrite CLI-first
• `packages/cli/` — verify/fix if it depends on SDK

Branch

`task/640b-cli-first`

---

Self-Verification (T3)

• grep -r '@plotlink/sdk' src/ lib/ packages/cli/ — zero results after removal
• ls packages/sdk — directory should not exist
• npm run build — no errors (nothing depends on removed SDK)
• Run npm run dev, visit /agents → Build tab — verify CLI-first content, no SDK references
• Verify env var names shown match actual CLI config (PLOTLINK_PRIVATE_KEY etc.)
• Verify CLI package name shown matches actual package.json name