fix(monitor-list): tag list do not update

[louislam]

Summary

Force to retrieve the tag list when open the menu.

Hadn't touch this part previously, just realized that it was actually not implemented in reactive way.

Resolves #7057

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• ⚠️ If there are Breaking change (a fix or feature that alters existing functionality in a way that could cause issues) I have called them out
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[Copilot]

Pull request overview

This PR addresses a UI consistency issue in the monitor list’s Tags filter dropdown by refreshing the available tag list when the dropdown menu is opened, so newly created tags can appear without a full page reload.

Changes:

• Add an openMenu emit to MonitorListFilterDropdown and trigger it on menu focus.
• Listen for the dropdown “open” event in MonitorListFilter to re-fetch tags via Socket.IO.

Reviewed changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated no comments.

File	Description
src/components/MonitorListFilterDropdown.vue	Emits an “open menu” event when the dropdown receives focus and opens the menu.
src/components/MonitorListFilter.vue	Hooks the tags dropdown open event to call getExistingTags() and refresh the tags list.

Comments suppressed due to low confidence (1)

src/components/MonitorListFilterDropdown.vue:36

• @focusin bubbles for every focus change inside the dropdown (button -> menu items, etc.). With the new openMenu() handler this will emit openMenu repeatedly while the menu is already open, which can trigger repeated tag fetches / extra socket traffic and may cause re-render/focus glitches. Consider emitting only when transitioning from closed -> open (e.g., guard on this.open before emitting) or move the handler to a non-bubbling event/element so it fires once per open.

        openMenu() {
            this.$emit("openMenu");
            this.open = true;
        },