StaticChart
===========

Server-rendered chart wrapper. ``<static-chart>`` fetches a
base64-encoded SVG from a JSON endpoint and renders it as an
``<img>``. Use it for charts that are produced on the server
(matplotlib pipeline) rather than as interactive Highcharts
charts. The ``<loading>`` overlay is shown for the duration of
each fetch.

The endpoint must return
``{"status": true, "data": "<base64-encoded SVG>"}``. The
component embeds that payload as a
``data:image/svg+xml;base64,...`` URL.

Range buttons
-------------

The header above the chart shows six built-in range buttons.
Clicking one sets the ``date_from`` form value to the
corresponding moment and re-fetches:

* ``1m`` -- 1 month back
* ``3m`` -- 3 months back
* ``6m`` -- 6 months back
* ``9m`` -- 9 months back
* ``YTD`` -- start of current year
* ``1y`` -- 1 year back

The chosen range is sent to the endpoint as
``date_from=YYYY-MM-DD``.

Date-range form
---------------

When ``hasForm`` is ``true``, the component also renders two
``<input type="date">`` fields (``dateFrom`` and ``dateTo``).
Changing either triggers an immediate re-fetch with both
values posted as ``date_from`` / ``date_to``.

Component accepts following params:

* ``url`` (required) -- JSON endpoint that returns
  ``{"status": true, "data": "<base64 SVG>"}``.
* ``hasForm`` -- Boolean flag; when ``true``, renders the
  date-range form alongside the range buttons (default
  ``false``).