fix(street-level): links keep the recipient's preferences; aim under the screen centre

Review fixes for gekh's #1113 round:
- a link runs show_street_level with origin 'programmatic', so its source
  switch and layer are not saved as the recipient's preferences;
- with no place named, the action looks under the screen centre
  (aim 'screen-centre', armed false), keeps the sky refusal and leaves a
  link's armed point alone;
- an armed OPEN aimed at the sky opens nothing instead of the far link point;
- an imagery-stage failure is spoken as an error, missing imagery as missing
  (street.nearestOutcome); the card says "the view centre" in the interface
  language;
- every photo the action opens reveals its panel, and revealPanel scrolls the
  panel into view in the phone sheet;
- embed: EXPAND survives embed's own clean view, the lifted photo hides in
  cockpit, recording and scene playback, and a failed photo step closes the
  earlier photo before the view flies;
- links pasted into an open tab run their street-level step after the
  restore settles; a superseded start link does not;
- Mapillary's nearest search gives up after 12 s, body included.

docs/CURRENT-STATE.md

@@ -4483,26 +4483,35 @@ app.
 (voice and typed; `src/voice/gevActions.js`) is one call: it checks the
 source has its key (a keyless source explains itself and changes nothing, as
 a chip does), flies to the place at street framing and waits for arrival (a
-name, coordinates, a pointed spot, a numbered item, or nothing for the view
-centre), switches to the map the source needs (Google Street View: Google 3D),
+name, coordinates, a pointed spot, a numbered item, or nothing for the
+ground under the screen centre, as OPEN uses: `aim: 'screen-centre'` with
+`armed: false`, so sky refuses and a link's armed point is neither used nor
+dropped), switches to the map the source needs (Google Street View: Google 3D),
 lights that source through `setLayerParams` with origin `voice` (one source at
-a time, kept in the share link like a chip click), turns the layer on and
+a time, kept in the share link like a chip click; a link runs the action with
+origin `programmatic`, for the source switch and the layer, so it never writes
+the recipient's saved layer state), turns the layer on and
 calls `openNearest`. `provider` is `google` for "Street View", `mapillary`,
 `kartaview` or `panoramax` by name, else the lit source. Stages fail separately (`location`, `view`, `map`,
 `provider`, `layer`, `key`, `imagery`; `view` when cockpit, clean view,
 recording or scene playback hides the panel, checked after the flight and
 before anything switches or loads; embed mode exempts its own clean-view
 class because the photo is lifted above the globe; an empty `imagery` result names a
-narrowing 360°/flat or SINCE filter the source honours, as `filter`) and a
+narrowing 360°/flat or SINCE filter the source honours, as `filter`;
+`noImagery` marks an empty result, `imageryError` a source or viewer failure
+and `aim: 'sky'` a sky centre, from the layer's `street.nearestOutcome`) and a
 newer turn retires the lookup
 (`openNearest`'s `signal` option), so nothing opens after the user moved on.
 For a source without a coverage layer the lookup widens to 250 m
 (`NEAREST_RADIUS_MAX_M`; Google honours it, Mapillary's API caps at 50 m);
-clicks keep 50 m. Mapillary's search asks for 100 photos, the API's most: it
+clicks keep 50 m. Mapillary's search gives up after 12 s, body included
+(`NEAREST_TIMEOUT_MS`), and asks for 100 photos, the API's most: it
 returns the radius's photos in no particular order and cuts them at the limit
 first, so the distance sort and the imagery filter run over the spot's photos.
 On a phone the panel sits in the Cameras tab sheet: a photo that opens, and a
-link that arms, open that sheet (`revealPanel`). The layer exposes `requiredMapStack(id)` and
+link that arms, open that sheet and scroll the panel into view
+(`revealPanel`); every photo the action opens reveals the panel again, also
+one the user had collapsed. The layer exposes `requiredMapStack(id)` and
 `providerStatus(id)` for callers that must decide before the panel lists a
 source, and `coverageLines(id)` (the lines a provider draws now, current and
 stale tiles, as `[lon, lat]` parts) for diagnostics and the browser gate,
@@ -4513,10 +4522,15 @@ source and point, defaulting to where the camera looks; a `google` source
 brings `map: photoreal` and refuses another map; not with `follow`), links as
 `sl=<source>,<lat>,<lon>`; `show_in_gods_eye_view` accepts it, the globe panel
 applies it through the action, and a plain link runs the action once restored
-(one shot: the rewritten hash drops `sl`). In embed mode the rail holding the
+(one shot: the rewritten hash drops `sl`). A link pasted into the open tab
+runs it after its restore settles (`gev:share-navigation-restore-settled`),
+and a start link whose restore a newer one superseded never runs. In embed mode the rail holding the
 panel is hidden, so an open photo moves to an overlay on the globe
 (`sl-viewer-wrap-embed`) and back when it closes; Esc closes it (in full
-screen, Esc leaves full screen first). Image-loading failures render inside
+screen, Esc leaves full screen first). EXPAND stays open under embed mode's
+own clean view; cockpit, recording and scene playback hide the overlay. A
+posted view whose photo step fails closes the earlier photo before its
+camera flies. Image-loading failures render inside
 the embedded overlay, since the panel's error region is hidden with the rail.
 A caller's abort is
 honoured through the viewer's mount and load, not just the lookup, and only
@@ -4529,8 +4543,9 @@ link never loads a photo from a source that bills every load
 (`billedPerImage` on the provider; Google): the action runs with
 `autoOpen: false`, arms the lookup on the layer (`armNearest`: the link's
 point and radius, consumed only by the next OPEN press (`aim:
-'screen-centre'`), and only while the view centre is within 1 km of the point
-(`ARMED_REACH_M`; a user who moved on opens what the view shows); any other lookup, open, close, disable, its source
+'screen-centre'`), and only while the ground under the screen centre is within
+1 km of the point (`ARMED_REACH_M`; a user who moved on opens what the view
+shows) or cannot be picked; a sky centre refuses; any other lookup, open, close, disable, its source
 switched off or its map leaving drops it), opens the panel and a toast
 points at OPEN GOOGLE STREET VIEW. Only the panel page's own link (inline
 embed) for a tool result issued in the last 5 minutes, and posted views, open