Addresses a portion of #10619, 2.6 Selection, highlight & inspection

[jorge-ferreira-pii]

Addresses a portion of #10619

2.6 Selection, highlight & inspection

Feature	GUI	Web	Status
Inspector editing	Descriptor::getEditors / getActions	set_property / trigger_action commands; editable properties become inline fields or dropdowns (X/Y, orient, placement status, master), object actions run from the toolbar (e.g. Delete behind a styled confirm modal) filtered by a blocklist, and rejected edits surface the reason via a toast — where the Qt GUI reverts silently	❌ → ✅
Highlight groups	16-group HighlightSet colored by Painter::kHighlightColors	highlight / unhighlight / clear_highlights commands with a 4×4 color-picker popover and a tinted badge; the server keeps highlight_groups plus derived overlay shapes (rects and flight lines for unrouted nets), and the 16-color palette is served in the tech response. Note: 16 groups, not 8 as the issue states	❌ → ✅
Selection browser	selectHighlightWindow (2 tabs)	Selection Browser panel (Windows menu) with Selected/Highlighted tabs and live counters, substring filter, sortable columns, and per-row zoom-to / de-select / inspect resolved by stable server index	❌ → ✅
Selection animation	selectionAnimation (QTimer 300 ms, outline weight cycling 1→2→3 px with a brush flash, 6 repeats)	client-side animateSelection replicating the Qt cadence on a Leaflet path with no per-tick layout repaint; triggers on multi-selection cycling and on selection-browser row hover (continuous), and respects prefers-reduced-motion by falling back to a single pulse	🟡 → ✅
Auto-connectivity	Ctrl+LeftClick → selectHighlightConnectedNets	Ctrl/Cmd+click sends show_connectivity; the server pulls the clicked instance's SIGNAL nets into the selection and reports connected_added (surfaced as a toast), with unrouted nets rendered as flight lines in the overlay	❌ → ✅
Hover pre-highlight	—	web-only: hovering the layout outlines the object under the cursor before selection; the issue attributes this to the Qt GUI, but it is a Web addition	✅ (web-only)

[gemini-code-assist]

Code Review

This pull request introduces a new "Selection Browser" component to the web interface, providing parity with the Qt GUI's Selected/Highlighted tabs, and adds support for server-backed property editing, highlight groups, selection animations, and coordinate-transform synchronization. On the backend, it implements corresponding WebSocket handlers and enhances shape collection to support flight lines for unrouted nets. The review feedback suggests optimizing the Selection Browser by checking its visibility state before refreshing to prevent redundant background network requests, and clearing any pending debounced refresh timers upon container destruction to avoid potential memory leaks.

[gemini-code-assist]

To prevent unnecessary background network requests and DOM rendering when the Selection Browser tab is hidden, the refresh method should check the visibility state (this._visible) before proceeding.

Suggested change

	refresh() {
	if (isStaticMode(this._app) || this._inFlight) return;
	refresh() {
	if (!this._visible || isStaticMode(this._app) || this._inFlight) return;

[gemini-code-assist]

When the GoldenLayout container is destroyed (e.g., when the user closes the Selection Browser tab), any pending debounced refresh timer (this._pendingRefresh) should be cleared. Failing to do so can cause the timer to fire on a destroyed component, leading to errors and memory leaks.

        // GoldenLayout tab visibility — skip background refreshes.
        container.on?.('show', () => {
            this._visible = true;
            this.refresh();
        });
        container.on?.('hide', () => {
            this._visible = false;
        });
        container.on?.('destroy', () => {
            this._visible = false;
            if (this._pendingRefresh !== null) {
                clearTimeout(this._pendingRefresh);
                this._pendingRefresh = null;
            }
        });