Fix import network filtering for account and project scope - #13836

Summary

Fixes #12685.

The unmanaged instance import wizard now lists networks in the ownership scope selected by the root administrator and cannot retain a network mapping from a previously selected owner.

This is a focused 4.22-based replacement for the project-network fix attempted in #12854. It contains only the two affected UI components and their unit tests, without the unrelated backend, schema, packaging, or formatting changes currently present in that PR.

Problems

The existing import wizard has four related owner-scope problems:

1. ImportUnmanagedInstance exposes a project selector but does not pass projectid to MultiNetworkSelection. Consequently, listNetworks runs without the selected project and project networks are not listed, as reported for 4.22.0 in UI: Import VM wizard doesn't list the project networks #12685.
2. The network selector watches account changes only. It does not refetch for domain or project changes, and it deliberately skips the request when the account is cleared. This can leave networks from the previous owner visible.
3. Existing NIC-to-network mappings are retained while the ownership scope changes. A network selected for the root-admin account can therefore remain in the form after switching to another account or project.
4. Network requests are not sequenced. If an earlier request completes after a later owner-scope request, its response can overwrite the current network list.

Changes

• Pass the selected projectid into MultiNetworkSelection.
• Build mutually exclusive listNetworks owner parameters:
  • projectid for project imports;
  • domainid and account for account imports;
  • neither for the default root-admin scope.
• Clear conflicting account/domain/project form fields when the administrator changes target ownership.
• Clear NIC network mappings immediately whenever the owner scope changes.
• Refetch when zone, domain, account, or project changes, including when a value is cleared.
• Retain the existing debounce for account text input.
• Ignore responses belonging to an older owner scope.
• Clear pending timers and invalidate requests when the component is unmounted.

User impact

When a root administrator imports an unmanaged instance:

• the default scope lists the administrator-visible networks;
• selecting an account and domain lists networks for that account scope;
• selecting a project lists networks for that project without mixing account/domain parameters;
• switching scopes clears any previously selected network before loading the new allowed list;
• a delayed response from the previous scope cannot restore stale networks.

The API remains the authorization boundary; this change makes the UI use the selected target scope consistently and prevents submission of stale UI mappings.

Validation

• MultiNetworkSelection.spec.js: five tests covering account/domain parameters, project precedence, domain refresh, clearing an account and stale mapping, and out-of-order responses.
• ImportUnmanagedInstance.spec.js: two tests covering mutually exclusive account/domain/project transitions and NIC mapping reset.
• Targeted unit tests: 7 passed.
• Targeted ESLint: passed.
• git diff --check: passed.

The project-network failure is reported against a live 4.22.0 environment in #12685. The additional stale-state and request-order cases are verified deterministically by the new unit tests; this PR does not claim a separate live 4.22 deployment test.