Table: support configuring initial Tab focus target (e.g. first column header)

[coolassassin]

Provide a general summary of the feature here

With roving tabIndex, first Tab into <Table> uses useSelectableCollection + GridKeyboardDelegate.getFirstKey(), which targets the first body row/cell. Apps that need first Tab on columnheader (sortable headers, WCAG patterns) must manually fight focusedKey, grid tabIndex={0}, and per-cell tabIndex overrides.

🤔 Expected Behavior?

Prop such as initialFocusTarget="firstColumnHeader" (or autoFocus="firstHeader") that sets initial focusedKey to the first column and moves DOM focus accordingly.

😯 Current Behavior

On the first Tab into a RAC <Table>:

While focusedKey is null, the [role="grid"] gets tabIndex={0}.
onFocus calls getFirstKey(), which picks the first body row (and with focusMode: 'cell' — the first body cell). Column headers are not used as the initial target.
Items get tabIndex={0} only when their key matches focusedKey; everything else is -1.
There is no prop to start Tab on the first columnheader, and

does not expose keyboardDelegate to override this.

Result: first Tab lands on the grid or a body cell, not the header. Apps that need header-first Tab must patch tabIndex and focus manually.

💁 Possible Solution

useSelectableCollection (onFocus ~366, tabIndex ~594), GridKeyboardDelegate.getFirstKey, TableKeyboardDelegate (columns are isCell but excluded from getFirstKey).

🔦 Context

Table with header + body, Tab from outside → focus lands on first body cell, not first columnheader.

Workaround for today:
Custom marshal + tabIndex overrides in app code (react-aria-components Table consumers).

💻 Examples

No response

🧢 Your Company/Team

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🕷 Tracking Issue

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