feat: capitalize first character in create new group text field

[codacy20]

PR Summary: Auto-capitalize first character in "Create New Group" text field

Problem

When tapping the + button under "Move to Group" to create a new group/category, the keyboard appeared without sentence capitalization — the user had to manually capitalize the first letter of the group name.

Root Cause

ClipboardTextField was building KeyboardOptions with only imeAction set, leaving capitalization unspecified (defaults to KeyboardCapitalization.None). This propagated all the way down to the TextField composable shown in the dialog.

Changes

• ClipboardTextField.kt — Added a capitalization: KeyboardCapitalization parameter (default None) and wired it into the KeyboardOptions passed to RYTextField2. This keeps the change opt-in and non-breaking for all existing callers (e.g. URL fields).

• TextFieldDialog.kt — Added a capitalization parameter (default None) to the deprecated String-based overload and forwarded it to ClipboardTextField.

• FeedOptionDrawer.kt — Passes KeyboardCapitalization.Sentences to the "Create New Group" TextFieldDialog, so the keyboard auto-capitalizes the first letter when opening the dialog from the feed options drawer.

• SubscribeDialog.kt — Same fix applied to the "Create New Group" TextFieldDialog in the subscribe/add feed flow.

Scope

Only the two group-name entry dialogs are affected. All other ClipboardTextField usages (feed URL input, etc.) retain KeyboardCapitalization.None since no capitalization argument is passed.

[codacy20]

@JunkFood02 mind reviewing this?