feat(places): link an expense to a place, the way bookings already do (#1917)

* feat(places): link an expense to a place, the way bookings already do

Recording what a museum ticket or a guided tour cost meant leaving the place,
opening the Costs tab and typing it in again — while a booking has had a Costs
block in its own form all along.

The place form now carries that block. Same component, same flow: with nothing
linked it offers Create expense, which saves the place and then opens the Costs
editor for a new expense pointing at it; once linked it shows the expense with
edit and remove. budget_items gains place_id beside the reservation_id it
already had, with the same nullable FK and the same ON DELETE SET NULL. Desktop
and phone both, and the mobile editor carries the link through its own save path
rather than the desktop one.

The expense belongs to the place, not to a day assignment, so a place sitting on
five days is not five tickets. Hanging it off the assignment would have meant
adding a place to three days quietly creating three expenses and removing a day
quietly deleting one.

Deleting a place takes its expense with it in the same transaction and announces
it, on every path that deletes a place: REST, both MCP tools and the plugin RPC.

Closes #1298

* test(places): teach the RPC stubs about linkedExpenseIds

The delete paths read the linked expense before the place is gone, so the two
hand-built PlacesService stubs threw on the new method instead of reaching the
hook, the remove and the broadcast — four failures out of one missing line.

wiki/Budget-Tracking.md

@@ -59,6 +59,12 @@ Click any editable cell to edit it inline. Drag the grip handle to reorder items
 
 Add a new item using the inline **add row** at the bottom of each category table.
 
+### Expenses linked to a booking or a place
+
+An expense can hang off a **booking** (reservation or transport) or off a **place** — both offer a **Create expense** button in their form, which saves the record first and then opens the expense editor for it. A linked expense is an ordinary expense: it takes a payer, a split, a date and a currency like any other, and it shows up in the settlement.
+
+Deleting the booking or the place deletes its linked expense with it. Removing the expense from the record's Costs block deletes only the expense and leaves the record standing.
+
 ## Splitting costs
 
 The **Persons** column behaves differently depending on the trip:

wiki/Places-and-Search.md

@@ -79,6 +79,14 @@ Type or paste a `lat, lng` pair (e.g. `48.8566, 2.3522`) into the **Latitude** f
 
 Two inline warnings are shown when editing times: one if the end time is set to a value before or equal to the start time, and one if the times overlap with another place already assigned to the same day.
 
+## Costs for a place
+
+With the [Costs/Budget addon](Budget-Tracking) enabled, the place form carries the same **Costs** block that bookings and transports have. **Create expense** saves the place and then opens the Costs editor for a new expense linked to it — the museum ticket, the guided tour, the entry fee. Once linked, the block shows that expense with edit and remove actions.
+
+The expense belongs to the **place**, not to a day. Putting the same place on several days does not multiply it: you bought the ticket once. If you really pay each time, add a second expense from the Costs tab.
+
+Deleting the place deletes its linked expense too, the same way deleting a booking does.
+
 ## Custom place image
 
 By default a place's thumbnail is fetched automatically (from Google/OpenStreetMap when the place was imported or matched, otherwise a category icon). To use your own photo instead, open the place's detail panel and click its round thumbnail — pick an image and it becomes that place's thumbnail everywhere (list, map marker, itinerary, PDF export and shared trips). A small remove button on the thumbnail clears the custom image and restores the automatic default. Accepted formats are JPG, PNG, GIF and WebP (HEIC is converted automatically), up to 20 MB.

wiki/Reservations-and-Bookings.md

@@ -73,7 +73,7 @@ Click **Add** (or the + button) in the Reservations panel. Fill in the form:
 9. **Hotel-specific fields** — shown only for Hotel type, immediately after status: hotel place, check-in day, check-out day, check-in time (window start and end), and check-out time. See [Accommodations](Accommodations)
 10. **Notes**
 11. **Files** — attach from your device (PDF, Word documents, text files, images) or link an existing trip file. Files added before saving are uploaded automatically after the reservation is created
-12. **Price and budget category** — shown only when the Budget addon is enabled. Entering a price greater than zero automatically creates a linked budget entry. See [Budget-Tracking](Budget-Tracking)
+12. **Costs** — shown only when the Budget addon is enabled. Instead of a price field, the form carries a **Create expense** button: it saves the booking and then opens the Costs editor for a new expense linked to it, so the expense gets a payer, a split and a date like any other. Once linked, the block shows that expense with edit and remove actions. See [Budget-Tracking](Budget-Tracking)
 
 <!-- TODO: screenshot: Create Reservation modal -->