[Feature] Dashboard toggle to include pending transactions in period totals

[Luis2EMP]

Problem

v0.14.0 (#507) introduced the pending/posted transaction lifecycle, and dashboard period totals now count only posted transactions. Changing the expected value in the income and expenses totals, unconditionally, with no option to opt out.

While a bill you know is coming could arguably pollute the totals, the inverse question is equally valid for those who enter upcoming transactions deliberately in order to plan with the dashboard. Aside from that, it affects the usability of the dashboard for users of bank sync, who have no control over the status of synced transactions (at least for some credit card Pluggy-synced transactions).

The "Period Transactions" and "Spending by Category" cards embedded in the Dashboard expose all transactions; the inconsistency between what is shown (all the transactions) and what is accounted in the monthly incomes/expenses can be misleading without indication.

Proposed Solution

An inline toggle on the dashboard controlling whether the period totals count posted transactions only or all transactions, similar to the Balance | Activity toggle added to the cash-flow calendar in #485.

• Two states: All (default) and Posted
• Defaults to All as expected from previous versions
• Preference persists across sessions
• Applies to the dashboard period cards and their drilldowns, so the two stay
  consistent with each other as established in fix: align dashboard drilldown totals #379
• Small icon or slightly faded/different color for pending transactions when in All state in the cards and in their drilldowns. Also maybe adding a column for Period Transactions with the status.

Alternatives Considered

One alternative would be a global setting in "Administration" settings menu. It makes some sense, since it is closely related to"Accounting" settings, also considering that, ideally, the preference persists across sessions. However, it is has more friction to reach for something users may want to change while looking at the dashboard.

Additional Context

Scoped deliberately to the dashboard, since based on #507 it appears to be the
only interface where posted/pending currently has an effect.

Running self-hosted v0.14.1, upgraded from v0.13.9.