Support split-domain Alexa auth/runtime for EU accounts

[6leonardo]

Summary

• add amazon_local config for local marketplace/runtime routing
• keep amazon_domain for auth/token exchange
• auth flow supports --domain (base) + --country (marketplace), aligned with alexa-cookie-cli usage
• improve CSRF discovery with fallback hosts
• improve history/activity CSRF + privacy endpoint fallback domains
• update README with new auth flow and config fields

Why

EU/IT accounts often authenticate via amazon.com but require local/runtime endpoint handling. This fixes mixed-domain behavior and reduces CSRF/history failures.

Tested

• alexacli devices -v
• alexacli command "turn on lights" -d "Living Room" -v
• alexacli history -v (fallback behavior)

Config example

{
  "refresh_token": "Atnr|...",
  "amazon_domain": "amazon.com",
  "amazon_local": "amazon.it"
}

[Copilot]

Pull request overview

Adds split-domain support so EU accounts can authenticate/token-exchange against one Amazon domain while routing marketplace/runtime/API traffic through a local domain, improving CSRF and history/privacy endpoint reliability.

Changes:

• Extend config to include amazon_local alongside amazon_domain, with sensible fallback behavior.
• Add NewClientWithLocal(...) and update runtime/CSRF/history endpoint routing to prefer the local domain with multiple fallbacks.
• Update CLI auth flow + README to document the split-domain login/config approach.

Reviewed changes

Copilot reviewed 5 out of 5 changed files in this pull request and generated 2 comments.

Show a summary per file

File	Description
internal/config/config.go	Adds amazon_local to config and defaults it to amazon_domain when omitted.
internal/api/client.go	Introduces local-domain routing, adds CSRF/history fallback hosts, and adjusts regional endpoint selection.
cmd/alexa/root.go	Constructs API client using amazon_domain + amazon_local.
cmd/alexa/auth.go	Adds --country (local domain) to browser auth flow and persists it as amazon_local.
README.md	Documents split-domain auth flow and new config fields.

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[Copilot]

The new --country flag defaults to amazon.it, which means running alexacli auth with no flags will save AmazonLocal=amazon.it and initialize the API client against the IT/EU runtime endpoints even for US accounts. This can break device listing/commands for users who previously relied on the default amazon.com behavior. Consider defaulting --country to an empty string (or amazon.com) and normalizing after flag parsing (e.g., if empty then set to domain) before calling runBrowserAuth/NewClientWithLocal and before saving config.

[Copilot]

GetCustomerHistoryRecords now hard-codes Accept-Language to Italian (it-IT,...). This will send the wrong locale for non-IT accounts and can affect server-side routing/CSRF behavior. Use the client’s derived locale (e.g. c.locale() / c.localDomain()) to build this header instead of a fixed value.

Suggested change

	req.Header.Set("Accept-Language", "it-IT,it;q=0.9,en-US;q=0.8,en;q=0.7")
	if locale := c.locale(); locale != "" {
	req.Header.Set("Accept-Language", locale)
	}