fix(tours): search along a tour through the places index along the line, and name what could not be searched (PLN-02, CW-05)

The search along a tour found nothing. It asked the places index for all
kinds of a stretch at once, above the 100 rows and 200 characters of terms
the index takes, so the index refused and every stretch went to the public
Overpass mirrors, which do not answer from this server. Now the index is
asked in small circles strung along the line, one request per kind and
circle within its limits, and an empty circle counts as an answer, so a
city walk lists its sights, museums, parks, cafes, restaurants and markets
in well under a second. The kinds the index does not know (viewpoints,
huts, drinking water, toilets and the like) are asked of Overpass along the
whole line at the same time, one query per stretch of up to 50 km, three at
a time, each with a short deadline of its own; a line past 400 km is
searched along its start and says so. When the index answers no circle at
all, its kinds go to Overpass beside the others instead of after them. A
kind no source could be searched for is named in a calm notice above the
list instead of reporting nothing found, and the reason is written to the
log. Unnamed taps, toilets, shelters, picnic spots, viewpoints, summits,
slipways and repair stands stay in the list and on the map under the name
of their kind; an unnamed garden, cafe or memorial is left out. The places
nearest the line are kept when there are more than sixty, listed from the
start, with the opening hours the source has.

A walk's parks are parks and gardens only, and its museums are museums
and galleries only, no longer the beaches, summits, theatres and cinemas of
the map's explore buttons; a water park the index files under parks is not
one of them. The index also answers markets and summits. The explore
buttons keep their single request, and a search of several kinds that
would exceed the index limits is asked one kind at a time instead of being
refused. The MCP tool search_tour_pois and its wiki row describe the walk
kinds and the new unavailable list, and the OVERPASS_TIMEOUT_MS row says
the search along a tour keeps its own shorter deadline.

server/.env.example

@@ -66,7 +66,7 @@ DEMO_MODE=false # Demo mode: resets data hourly
 # NOMINATIM_URL=https://nominatim.openstreetmap.org # Custom HTTP(S) Nominatim base URL for every geocoding call the server makes: place search, reverse lookup, place details and the Atlas region fill. When set it REPLACES the public service with no fallback, so whatever answers has to speak the Nominatim API (/search, /reverse, /lookup) and hold the coverage you expect. TREK keeps its ~1 request per second spacing whichever instance answers. Unset/blank uses the public default.
 
 # OVERPASS_URL= # Custom Overpass endpoint(s) for the map POI "explore" search, comma-separated. When set, REPLACES the bundled public mirrors — point it at an internal/self-hosted Overpass instance when the public ones are unreachable from your network. Non-http(s) entries are ignored. If you don't self-host Overpass but the public mirrors throttle you, setting APP_URL also gives outbound requests a unique User-Agent the mirrors rate-limit less.
-# OVERPASS_TIMEOUT_MS=25000 # Per-endpoint timeout (ms) for Overpass POI requests; slower endpoints are abandoned so a faster mirror wins. The query itself gives Overpass 20 seconds of work, so a lower value hangs up on answers that were still coming. Raise it for a slow self-hosted instance. (default: 25000)
+# OVERPASS_TIMEOUT_MS=25000 # Per-endpoint timeout (ms) for Overpass POI requests; slower endpoints are abandoned so a faster mirror wins. The query itself gives Overpass 20 seconds of work, so a lower value hangs up on answers that were still coming. Raise it for a slow self-hosted instance. The Tours search along a tour does not read it: it gives Overpass 10 seconds of work and waits 12. (default: 25000)
 
 # TREK_PLACES_ENABLED=false # Whether place search asks the TREK Places API at https://places.liketrek.com: suggestions, the full search, the category buttons on the map, the Road trip search along the route, import geocoding and offline downloads. It is on by default and has no switch in the admin panel, because whether searches leave the instance is a deployment decision. Set false to search the way it did before 4.3.0 (OpenStreetMap, or your Google/Amap key) and send nothing to that host. (default: true)
 # TREK_PLACES_URL=https://places.liketrek.com # Base URL of a copy of the Places API you run yourself; it has to answer the same /v1 API. Read from configuration rather than typed by a user, so an address on your LAN or Docker network works without ALLOW_INTERNAL_NETWORK. (default: https://places.liketrek.com)