Merge upstream/main: Street View rework meets i18n

Upstream's Street View rework (second imagery provider, one source at a
time, OPEN STREET VIEW button, key-alternative guidance) rewrote exactly
the street-level regions this branch localizes.

Resolved as upstream logic + re-applied localization:

- keySetupCore: new unlock copy kept as msg() data; added
  keySetupAlternativeKeyNames() returning machine values (registry key
  names) so key-setup core stays English while presentation localizes.
- New src/ui/keyGuidance.js: localized key-guidance composer shared by
  layerPanel and streetLevelPresentation (requirement sentence plus the
  "or light X to use your Y key" alternatives tail, placeholders only).
- streetLevelPresentation: keyGuidance()/presentNearest()/presentMeta
  relocalized (t/tn + formatNumber instead of toLocaleString);
  renderModes and month-precision dates kept from upstream.
- layer-panels.html: upstream row ids, sl-meta-row and the new button
  kept, data-i18n hooks re-applied (incl. OPEN STREET VIEW fallback).
- es/ru catalogs: 13 new keys, stale unlock key replaced in place.

npm run i18n: complete for es and ru. npm test: 6345/6347; the one
failure (devFreshDotenv provenance) also fails on plain upstream/main
and on the pre-merge tip here - this machine leaks OPENAI_API_KEY into
spawned children with a replaced env, so it is environmental.

CHANGELOG.md

@@ -107,9 +107,18 @@
 
 ## [Unreleased]
 
-- Keep later satellites when a TLE catalog entry is missing an orbital line.
-  The parser skips the incomplete set and resumes at the next complete named
-  set, instead of losing the rest of the group (#906).
+- Street Level: Google Street View is the second provider. On the Google 3D
+  map (Google's terms keep it off other maps), light its chip (off by
+  default: every panorama is billed to the Google Maps key, which needs the
+  Maps JavaScript API) and click a street, or press OPEN STREET VIEW, to
+  open Google's own panorama in
+  the panel, with its arrows, the address and month in the caption, a link
+  to Google Maps and FOLLOW. Share links carry it in the provider switches
+  (`r.google-1`). One provider is lit at a time (lighting one switches the
+  other off), Mapillary by default since it is free. Street View's panoramas
+  are all 360°, so the IMAGERY and SINCE filters and the legend apply to
+  Mapillary only and hide while GOOGLE STREET VIEW is lit; its globe marker
+  is a Google-blue view cone.
 
 - Add an experimental ChatGPT/Codex OAuth option for cloud voice in Provider
   Settings. API-key voice remains the default. Local sign-in can start from