Part of #145.
Fourteen files across seven feature areas that had no namespace yet: the
things create/edit modals and their history, the chore history detail and
edit modals, the activity feed, the points view and its redemption modal,
the project view with its selector and icon picker, the label view, the
advanced filter builder and the timer edit modal.
Seven new namespaces registered in `src/i18n/config.js` in one change
rather than one per PR, so the `ns:` array is touched once and my other
extraction PRs cannot conflict with this one. Namespaces stay
feature-scoped as described in #145; if you'd rather fold any of these
into `common` or `chores`, say which and I'll rework it.
Dictionaries: `history` 57 keys, `points` 50, `timer` 25, `projects` 16,
`things` 14, `filters` 13, `labels` 5.
English only — no translations, no behaviour change. Every t() value is
checked against this branch's base: the string must appear
character-for-character in the code it replaces (226 call sites).
Three values in `UserPoints` are matched loosely and worth naming. The
base builds the leaderboard heading and subtitle around a ternary —
`{mode === 'points' ? 'Points' : 'Tasks'} Leaderboard` and `Rankings based
on {…} during the selected time period` — so neither full sentence exists
contiguously in the source. Each key holds exactly what one branch
renders. The sentences are kept whole rather than split around the
ternary, since a sentence assembled from fragments cannot be reordered by
a translator.
