feat(workspace): add tool switches to the codeg-mcp popover

Rework the status-bar popover into something that can be acted on rather
than only read. The bar glyph is now as plain as its neighbours — no tone,
no count — and the state moves into a badge in the popover header. Below
it sit a three-column strip (agent sessions, running delegations, depth
cap) and one row per tool group, each carrying the icon the General
settings page uses for that same switch, a one-line description, and a
Switch that writes through. The footer keeps the Start action and opens
full settings on the General page, where these switches live in full.

That makes the popover a second editor for settings the General page
already owns, which is what the rest of this change is about:

- set_codeg_mcp_tool_group writes exactly the one key a switch owns. A
  whole-record write would lose a flip: automations and taskboard share
  a record and sit one click apart here, and delegation's record also
  holds the depth limit and the per-agent defaults.
- Both records serialize their writers behind a mutex spanning
  write -> re-read -> apply -> broadcast. Their keys are read in separate
  queries, so interleaved writers could otherwise leave the database
  correct while the runtime config settled on a value neither intended.
- Delegation now broadcasts delegation-settings://changed, and both
  General-page forms subscribe to their record's broadcast. A form left
  open across a popover toggle adopts it instead of reverting it on the
  next save, while a switch the user has already moved keeps its pending
  value.

Also makes "general" an addressable settings section — the desktop
transport otherwise falls back to Appearance — and adds the popover's
copy in all ten locales.