feat(ui): add label filter sync with URL query params

[puretension]

Fixes #14807

Motivation

WorkflowTemplates UI silently ignores label query parameters (e.g., ?label=key%3Dvalue) unlike Workflows list, breaking URL filtering and preventing custom UI links for filtered template views.

Modifications

• Added label query parameter sync with URL in WorkflowTemplates UI
• Combined URL updates and localStorage persistence in single useEffect
• Now matches Workflows list behavior for consistent filtering

ref-recorded-video.mov

Verification

• ?label=key%3Dvalue now properly filters WorkflowTemplates
• URL updates when changing filters in UI
• Filters persist on page refresh

Documentation

[eduardodbr]

tested locally with success

[puretension]

Hi @eduardodbr,

Thanks for approving! After implementing this fix,
I noticed we have duplicate label synchronization logic across multiple components:

Duplicate patterns found:

• workflows-list.tsx + workflow-template-list.tsx: Same useState + queryParams + localStorage logic
• cron-workflows/cron-workflow-list.tsx: Has labels state but missing URL sync
• reports/reports.tsx: Different queryParams pattern

Duplicated code pattern:

typescript
// Repeated in multiple files
const [labels, setLabels] = useState(() => {
    const queryParams = new URLSearchParams(location.search);
    const labelQueryParam = queryParams.getAll('label');
    return labelQueryParam.length > 0 ? labelQueryParam : savedLabels;
});

Proposal:

Would you be interested in a follow-up PR after this merges that extracts this
into a shared custom hook? This would:

• Eliminate code duplication
• Improve maintainability
• Standardize label filtering across all components

Let me know what you think!

[eiriklid]

Hey, I would really like to have this feature.

Is there any way I can contribute so that it can be released?