update data widgets documentation

[gjulivan]

Update Data Widgets docs to match Data Widgets 3.x (filtering, sorting, properties)

Why

The Data Grid 2 and Gallery docs still described the Filtering and Sorting tabs on the data widget itself. Since Data Widgets 3.0.0, grid-wide filtering and sorting are configured in the filter widgets and in Drop-Down Sort. A review against the widget source (Data Widgets 3.11.7) also found outdated captions, removed properties, and behavior descriptions that no longer match the widgets.

What changed

Filtering and sorting

• Data Grid 2: rewrote Grid Wide Filtering to point to the filters placeholder and the filter widget settings (Filter attributes / Attribute config set to Custom). Added a note that this changed in Data Widgets 3.0.0.
• Gallery: replaced the Filtering and Sorting sections with short sections that link to the filter widget pages and Drop-Down Sort. Removed the Advanced Options section (the toggle no longer exists).
• Drop-Down Sort: documented the current properties (Datasource to sort, Attributes, Empty option caption, screen reader captions).
• Removed four images that showed the old Filtering/Sorting tabs: gallery/filtering.gif, gallery/filtering.png, gallery/filter-region.png, gallery/sorting.png.

Filter widget pages (Text, Number, Date, Dropdown)

• Restructured to follow the Studio Pro tabs and groups, with exact captions and visibility conditions.
• Documented missing properties: Between-range properties (Date), Caption source, Search attribute, Empty selection caption, Filter input placeholder (Dropdown).
• Corrected Datasource to Filter (linked automatically from the containing data widget), Saved attribute (written, not read back), and default values.

Data Grid 2 Properties

• Rewrote the page to follow the current properties pane: General, Behavior, Personalization, and Texts tabs, plus Column properties.
• Documented about 30 missing properties, including the Texts tab, export settings, Store configuration in, Load more, and column min width.
• Fixed incorrect descriptions (column tooltip, dynamic cell class, Show number of rows).

Factual fixes on other pages

• Data Grid 2: pagination (three types, Position of pagination, Show number of rows), Drop-Down filter options and visibility, personalization settings, selection with Row click and double-click, runtime error text. Removed the outdated Performance and Troubleshooting subsections (Data Widgets 1.x, Atlas 2.x).
• Gallery: data source types, captions, Behavior tab placement, selection highlight color, Data Grid 2 link.
• Selection Helper: Filters placeholder and the None selected / Some selected / All selected captions; select all applies to the current page.
• Tree Node: Has children is an expression; infinite mode tip now refers to Start expanded; added Open node when and No data message.
• Data Widgets landing page: widget list matches the module packages; added minimum Studio Pro version (10.24.0).