Settings: delete every archived session at once

[jdrly]

Archived sessions only go away one at a time, through the sidebar's context menu. Once Settings > Archived holds a hundred-plus of them, clearing the list means a hundred-plus rounds of right-click, Delete, confirm.

This adds a Delete all button to the Archived page. It asks once, with the count, then deletes every archived session.

Summary

• Red Delete all button on Settings > Archived, bottom-aligned with the subtitle. Hidden when nothing is archived.
• The confirmation reuses the single-session "Delete session?" card. It deletes exactly the sessions that were archived when you clicked, so anything archived while the dialog is open survives.
• Each session goes through the existing deleteChat mutation, the same call the sidebar's Delete makes. No new RPC or wire change. Rows leave the page and the sidebar's Archived shelf as each delete lands.
• Failed deletes are counted into one toast: "Couldn't delete N archived sessions. Try again."
• widgets::ActionTone gains Danger: the dialogs' destructive fill at the standard settings button size.

Worth a look: the deletes run one mutation per session in a detached task, the same pattern as the sidebar's section archive. With 146 sessions that's 146 sequential calls. I kept it that way to avoid a new batch op, but I've only run it with 8.

Test plan

• cargo test --locked -p zeron-ui --lib -- --test-threads=1 (1675 passed)
• New delete_all_deletes_the_confirmed_archived_chats_and_reports_failures: only the confirmed archived chats get deleteChat, a chat archived after the dialog opened survives, and a rejected delete produces the toast
• cargo clippy -p zeron-ui --lib --tests: no new warnings in touched code
• Manual on macOS, dev build against an isolated mock engine: Delete all with 6 and 8 archived sessions, Cancel, rows leave the page and the sidebar's Archived shelf, the live session stays. Light and dark.
• Not checked: Windows, Linux, and a synced profile with archived sessions hosted on another device

Screenshots

Screenshots and a recording follow.

🤖 Generated with Claude Code

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[jdrly]

delete-all.mp4

[wingleeio]

Thanks! Capturing the id list when the dialog opens, one deleteChat per chat through the existing mutation, the count in the confirmation, and the in-flight guard all look right.

I pushed one commit (1276c60):

• Each captured id is rechecked against the live list right before its delete, so a chat unarchived after confirming (via Unarchive here or on another device) is spared.
• Escape closed Settings underneath the dialog, and since the page outlives Settings the stale dialog reopened with it. Escape now dismisses the dialog first, like Devices/Harnesses/Appearance.

Ran cargo check -p zeron-ui --all-targets and cargo test -p zeron-ui --lib merged with main — green.