Fix create payload route context

[seppegadeyne]

Summary

This fixes the create-order payload path so terminal swaps carry the same route context the web app sends when an order is created.

Changes:

• send website-compatible quote params (from_net, to_net, type=from) while keeping the existing network_from / network_to aliases
• include quote/route context in create payloads (trade_id, selected route amount_to, selected route fixed_rate)
• validate required create fields client-side before POSTing, so the TUI fails locally instead of calling the API with an incomplete payload
• add regression coverage for the quote params, create payload shape, and local missing-field validation

Why

For routes like USDC-Base -> QUBIC-Mainnet, the estimate succeeds but the order creation path can fail with:

api POST /v2/exchange/create: 400 {"error":"Missing required params: provider, address_to, from_currency, to_currency","code":"MISSING_PARAMS"}

The web app create flow sends the selected quote/route context explicitly. Mirroring that shape in the CLI makes the create request less ambiguous and prevents incomplete create payloads from reaching the API.

Verification

go test ./internal/api
go test ./...
make kyc-cli
./bin/kyc-cli --version

Local verification was run with Go 1.25.11.

[seppegadeyne]

Follow-up after local TUI testing:

• Fixed a regression where a free-text destination ticker/network (for example QUBIC-Mainnet) was cleared immediately after pressing Enter in the destination picker.
• Added TestFreeTextDestinationPersistsAfterPickerEnter to cover that picker flow.
• Re-ran go test ./... successfully.