fix(ui-table): fix caption for table to be responsive to sorting

[HerrTopi]

changes the Table caption prop from an auto-appended hardcoded English "Sorted by..." string to a consumer-supplied function (sortByHeader, sortDirection) => string, so the caption reflects sort state in a fully localizable way. In v1 this is non-breaking (caption accepts a ReactNode or a function), while v2 now requires caption to be a function (breaking change), with tests, docs, and the regression page updated accordingly.

TESTS_PLAN

• With a screen reader (NVDA/VoiceOver), sort a column and confirm the caption announcement reflects the new sort state and uses the consumer-provided (localizable) text, not a hardcoded English suffix.
• v1 only: pass a plain string caption → confirm it renders unchanged and no sort announcement fires (expected behavior); pass a function → confirm announcements fire on sort change.
• Confirm sort announcement only fires when the sort actually changes (no duplicate/repeat announcements).

INSTUI-5047

[github-actions]

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[github-actions]

Visual regression report

✅ No changes.

Status	Count
Unchanged	32
Changed	0
New	0
Removed	0

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[ToMESSKa]

• In v11.6 examples, there is no announcement which column the table is sorted by (see below)
• also there is no announcement when I change the sorting in the v11.6 examples

Can you please take a look at these?

[ToMESSKa]

• In v11.6 examples, there is no announcement which column the table is sorted by (see below)
• also there is no announcement when I change the sorting in the v11.6 examples

Can you please take a look at these?

@HerrTopi The title of the table (Top rated movies) is not announced in the v11.6 example.
Can you please fix that too?