fix(filters): don't auto-open the filter panel when only sorting a column

[skywalke34]

Description

List pages share a single django-filter form for both filtering and column sorting (the OrderingFilter o parameter). The filter panel's initial expanded state is driven by {% if ...form.has_changed %}, so sorting a column — which only adds ?o=... to the URL — flips has_changed() to True and auto-opens the filter panel even though no filter was applied.

This is most visible on the Asset (Product) list: clicking the Organization or Active (Verified) Findings column header reloads the page and the filter panel springs open. (Originally reported in #1811 and since regressed.)

Fix: add a small has_active_filters template filter that mirrors form.has_changed() but ignores the ordering field (o), and use it for the panel-expand condition on all list pages, in both UI trees:

• dojo/templates/ — new (Tailwind) UI — 17 templates.
• dojo/templates_classic/ — classic (default) UI — 18 templates (the same list pages, plus both filter panels on action_history.html).

Sorting is no longer treated as filtering, so the panel stays closed unless a real filter value is set.

This is intentionally narrow and low-risk:

• form.has_changed() itself is not modified, so nothing relying on Django's has_changed() semantics is affected.
• django-filter does not use has_changed() for filtering (it uses cleaned_data), so query/sort results are unchanged.
• The only observable effect is the filter panel's initial open/closed state.

view_finding.html uses a separate, hand-managed has_changed flag for similar-findings, and the condition in view_notification_webhooks.html is commented out — both intentionally left unchanged in both trees.

Test results

Added unittests/test_filter_tags.py covering has_active_filters:

• no params / sort-only (o=prod_type__name, o=-name) → not active (panel stays closed)
• a real filter (name=…) / filter + sort → active (panel opens)

Ran 6 tests in 0.017s
OK

• Verified end-to-end through the template engine that {% if form|has_active_filters %} renders the panel CLOSED for sort-only requests and OPEN when a filter value is present.
• Verified live on the new (Tailwind) UI: sorting the Asset list by Organization no longer opens the panel.
• Compile-checked all 18 modified classic templates parse correctly with the new {% load filter_tags %} + |has_active_filters.

Documentation

No documentation changes needed — UI behavior fix, no settings or model changes.

Known related issue (out of scope here): on tables enhanced by DataTables, clicking a sortable header briefly client-sorts the visible rows before the server-side ?o= reload replaces them (a momentary "flash"). That is the long-standing client-vs-server sort conflict also noted in #1811 and is intentionally not addressed in this PR.

Checklist

• Bugfix submitted against the bugfix branch.
• Meaningful PR name (may be used in release notes).
• Code is Ruff compliant (see ruff.toml).
• Code is Python 3.13 compliant.
• No model changes / migrations required.
• Added applicable unit tests.
• Fix applied to both the new and classic UI template trees.
• Add the bugfix label.

[skywalke34]

I was not able to set the bugfix label.