fix(a11y): Role.Button on all bare clickables, TextField label link, split-tunnel double-action

[Danialsamadi]

Summary

Builds on the TalkBack foundation from #45 to close the remaining WCAG 4.1.2 (Name, Role, Value — Level A) gaps found by a full audit of WhiteDnsScreen.kt.

• Split-tunnel app row — replaced .clickable + active Checkbox(onCheckedChange) with toggleable(role = Role.Checkbox) + Checkbox(onCheckedChange = null, clearAndSetSemantics {}), matching the ParallelTestConfigRow pattern. Previously TalkBack focused on both the row and the checkbox separately, firing onToggle() twice.

• ConnectButton — added role = Role.Button to .semantics(mergeDescendants = true) {} so TalkBack announces "Button" on the main action element.

• 23 bare .clickable elements — added role = Role.Button to every custom interactive element that used .clickable {} or .clickable(enabled) without a declared role. Includes: expand/collapse headers, ProfileIconButton, CompactActionButton, ResolverActionButton, LogActionButton, SectionCard toggle header, dropdown triggers, dismiss/close buttons for banners and dialogs, the footer Telegram link, copy-address row, and stat cards.

• WhiteDnsTextField label association — wrapped the Column(FieldLabel + BasicTextField) with semantics(mergeDescendants = true) so TalkBack announces the visible field label alongside the input field (WCAG 1.3.1 / 3.3.2).

• SectionCard non-collapsible icon — contentDescription is now null when collapsible = false, eliminating noise for screen reader users on static section headers.

WCAG criteria addressed

Criterion	Level	Impact
4.1.2 Name, Role, Value — missing role on 23 clickables	A	High
4.1.2 Name, Role, Value — split-tunnel double action	A	Critical
4.1.2 Name, Role, Value — ConnectButton role	A	High
1.3.1 Info and Relationships — TextField label link	A	Moderate
4.1.2 Name, Role, Value — non-collapsible icon noise	A	Minor

Test plan

• TalkBack: tap each interactive element and verify it announces "Button" (or "Checkbox" / "Switch" for toggles)
• TalkBack: verify split-tunnel app rows toggle once per tap and announce checked/unchecked state
• TalkBack: verify ConnectButton announces "Button" alongside its status label
• TalkBack: verify text fields announce the visible label when focused
• TalkBack: verify non-collapsible SectionCard headers are not announced as interactive
• Visual regression: all elements look unchanged

🤖 Generated with Claude Code

[iampedii]

@Danialsamadi Thank you for you MR.