feat(desktop): add "Delete all chats" button to the chat sidebar

[hashbender]

What does this PR do?

Adds a "Delete all chats" button to the desktop chat sidebar. It sits to the right of the existing new-chat (+) and folder-toggle controls in the recents header and permanently deletes every chat in the active profile, behind a destructive confirmation dialog that shows how many will be removed.

Before this, the only way to clear history was deleting chats one at a time (right-click → Delete, or the per-row trash in Settings → Sessions). There was no bulk affordance on the desktop, even though the backend and the web dashboard already had one.

Why this approach: the desktop's REST backend (hermes_cli/web_server.py) already exposes POST /api/sessions/bulk-delete — the same endpoint the web dashboard's bulk-select-then-delete flow uses. So this is a pure-renderer feature with no backend change: clearAllSessions pages the active-profile scope (the same rows the recents list shows) in ≤500-id chunks and deletes each page until the scope is empty, grouping ids by owning profile so each profile is cleared against its own state.db. It mirrors the maintainers' existing explicit-id bulk-delete design rather than introducing a new blanket endpoint.

Related Issue

No existing issue or PR — searched the tracker and open PRs first. Happy to open a tracking issue if preferred.

Fixes #

Type of Change

• ✨ New feature (non-breaking change that adds functionality)

Changes Made

• apps/desktop/src/hermes.ts — bulkDeleteSessions(ids, profile) bridge call to POST /api/sessions/bulk-delete, plus the BULK_DELETE_MAX_IDS (500) cap constant.
• apps/desktop/src/app/session/hooks/use-session-list-actions.ts — clearAllSessions(): page-and-delete loop, optimistic row + pin removal, authoritative refresh.
• apps/desktop/src/app/desktop-controller.tsx — clearAllChats wrapper that drops the open chat to a fresh draft and closes its runtime first (mirroring removeSession), wired to the sidebar.
• apps/desktop/src/app/chat/sidebar/index.tsx — the trash button (hover-revealed, destructive-red on hover) and the ConfirmDialog. Hidden in all-profiles and project-grouped views; only shown when the active scope has chats.
• apps/desktop/src/i18n/{types,en,ja,zh,zh-hant}.ts — sidebar.deleteAll strings.
• Tests: hermes.test.ts (bridge call shape + profile routing) and use-session-list-actions.test.tsx (pages & deletes, groups by profile, no-op when empty).

How to Test

1. Open Hermes Desktop with a few chats in the sidebar.
2. Hover the recents header — a trash icon appears to the right of + and the folder toggle.
3. Click it → a confirmation dialog shows the chat count. Confirm.
4. The list empties; archived chats (Settings → Sessions) and the new-chat draft are unaffected. Cancelling leaves everything in place.

Scope notes: deletes the non-archived chats of the active profile (pinned included; cron/messaging excluded, matching the recents list). The button hides in the all-profiles and project-grouped views.

Checklist

Code

• My commit messages follow Conventional Commits (feat(desktop):)
• I searched for existing PRs to make sure this isn't a duplicate
• My PR contains only changes related to this feature
• I've added tests for my changes
• I've tested on my platform: macOS 15 (Apple Silicon)

Verified locally: tsc -p . --noEmit clean, eslint clean, and vitest green for the new/changed specs and the i18n suites. (Python pytest tests/ is unaffected — this is a renderer-only change with no backend edits.)

Documentation & Housekeeping

• Documentation — N/A (no user-facing docs cover per-button sidebar affordances)
• cli-config.yaml.example — N/A (no config keys)
• CONTRIBUTING.md / AGENTS.md — N/A (no architecture/workflow change)
• Cross-platform impact — renderer-only React/TS; no OS-specific code paths
• Tool descriptions/schemas — N/A

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Mirror-of: NousResearch#55957
NousResearch#55957

[tenki-reviewer]

Review Complete
No issues found!

Risk: 🟢 Low (15/100) — no findings · 371 LOC across 11 files

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PR adds i18n localization support to the desktop app with translations for English, Japanese, Simplified Chinese, and Traditional Chinese, along with a new session-list refactor and improved desktop controller reactivity.

Files Reviewed (11 files)

apps/desktop/src/app/chat/sidebar/index.tsx
apps/desktop/src/app/desktop-controller.tsx
apps/desktop/src/app/session/hooks/use-session-list-actions.test.tsx
apps/desktop/src/app/session/hooks/use-session-list-actions.ts
apps/desktop/src/hermes.test.ts
apps/desktop/src/hermes.ts
apps/desktop/src/i18n/en.ts
apps/desktop/src/i18n/ja.ts
apps/desktop/src/i18n/types.ts
apps/desktop/src/i18n/zh-hant.ts
apps/desktop/src/i18n/zh.ts