fix(MultiselectInput+SelectInput): handle undefined and null values

[mgoetz-lion5]

Handle null and undefined values

[Copilot]

Pull request overview

This PR updates the SelectInput and MultiselectInput components to better handle externally-driven null/undefined model values by clearing internal selections and adding unit tests to validate these transitions.

Changes:

• Clear the currently selected option in SelectInput when modelValue becomes null/undefined.
• Make MultiselectInput’s model watcher treat non-array / empty values as “no selection”.
• Add unit tests covering external modelValue changes for both components.

Reviewed changes

Copilot reviewed 4 out of 4 changed files in this pull request and generated 3 comments.

File	Description
packages/core/src/components/inputs/SelectInput/SelectInput.vue	Clears selectedOption when the bound modelValue becomes null/undefined.
packages/core/src/components/inputs/SelectInput/SelectInput.spec.ts	Adds a test asserting the selection updates when modelValue changes externally (including null).
packages/core/src/components/inputs/MultiselectInput/MultiselectInput.vue	Updates initialization + watcher logic to reset selections when the external value isn’t a non-empty array.
packages/core/src/components/inputs/MultiselectInput/MultiselectInput.spec.ts	Adds a test for external modelValue transitions (including empty array and null).

---

💡 Add Copilot custom instructions for smarter, more guided reviews. Learn how to get started.

[mgoetz-lion5]

@copilot apply changes based on the comments in this thread

[Copilot]

@copilot apply changes based on the comments in this thread

Applied all three review changes in commit 8f59006:

1. SelectInput.spec.ts – Replaced the internal vue-multiselect modelValue assertion with a UI-level check (absence of has-content class) when modelValue is set to null, since vue-multiselect returns [] internally even for undefined single-select values.

2. MultiselectInput.vue onMounted – Added .filter(Boolean) (via flatMap) to eliminate undefined entries that can arise when keys in modelValue aren't present in optionsMap. Also switched the condition to Array.isArray(...) for explicit null/undefined safety.

3. MultiselectInput.vue defineModel – Widened the type to (string | number | boolean | null)[] | null | undefined so the public API typing aligns with the runtime behavior that already handles null/undefined values.