Improvements and fixes

The monitor chart now shows what a plant should have produced while it was offline. The week, month and year charts gain the same expected-production curve as the day chart.

• The monitor chart now shows what a plant should have produced while it sent nothing, marked "Expected (no connection)".
• Reference curves now break where the plant sent nothing, instead of drawing a straight line across the gap.
• On the export page, "Try it out" now provides ready-made terminal commands, a Python script and an AI prompt, with a reporting-only access token.
• A plant's components can now be searched and attached to a ticket while it is still being written.
• Large exports covering many plants now arrive faster.
• Every date range picker now offers "Last year", meaning the whole of the previous calendar year.