feat: fund + bridge — inbound USDC on-ramp (CCTP)

[anil-rome]

feat: fund + bridge — the "from home" USDC on-ramp (inbound CCTP)

Adds the Phase-2 funding commands from the approved SPEC (publishing/rome-mcp-cli/SPEC.md), the "from home" builder path.

What it adds

• rome fund <chain> --from <src> --amount <usdc> — bridge USDC → Rome native gas (CCTP, intent:gas).
• rome bridge <chain> --from <src> --amount <usdc> [--intent gas|wrapper] — general inbound; wrapper delivers wUSDC on Rome.
• One rail-agnostic engine (runInboundUsdc) that orchestrates @rome-protocol/sdk/bridge (quote → sign source burn → settle-auth if gas → register → poll). The SDK owns the protocol; the CLI owns the source-chain signing it leaves to the client.
• Actions: CLI-only, key-gated (ROME_EVM_KEY, env-only), never on MCP — enforced + tested. --dry-run previews with no spend.
• Source chains + RPCs + USDC addresses resolve from the registry (getBridge) — no hardcoding.
• Small --flag parser added to the CLI (positional invocations unchanged).

Verification (funded, on-chain)

• 55/55 unit tests (flow order · wrapper-skips-settle · dry-run · resolvers · key-gating · flag parser), typecheck clean, MCP smoke (actions absent from the tool list).
• Live dry-run against the real bridge-API (real quote, correct plan).
• Funded wrapper transfer txf_0639… (Sepolia → Hadrian, 0.5 USDC): approve 0xb1fe158e… + burn 0x8ecf70ab… → record complete (amountOut 500000), Solana mint 4sgh6xpB… to the recipient ATA; EVM-lane wUSDC.balanceOf on Hadrian confirms the credit.
• The gas-intent path is validated through registration (source burn + settle EIP-712 accepted by the API), but its final on-chain settle is currently gated on a bridge-side sponsor-worker fix (tracked separately) — the CLI itself is cleared; wrapper is the funded-verified rail in this PR. Gas closes once that lands.

Docs

• README reframed to the real two-layer surface (grounding read + actions) — fixes the stale "does not deploy or sign" from feat: Phase 2 contract layer — call / deploy / send #3.
• GUIDES: a "fund a wallet from another chain" recipe with real output.

Scope / follow-ups

• This PR = inbound CCTP. ETH/Wormhole-in and outbound (from-rome) are the next slice (each gets its own funded gate).
• Follow-up: move the bridge-API base into registry bridge.json (chain-first — today it's --bridge-api/ROME_BRIDGE_API/devnet-default).
• Follow-up: tighten the fund/bridge route assertion to the observed route strings.