Show a live picture on a camera tile, run an action from the alert button, roll long media titles, and keep full-page tiles in their own colour (0.2.91)

Live picture (issue #4): a camera or image tile on a Guition takes
Display -> Live picture with a pace of 15 or 30 s. The camera tiles of a
page share one download: the screen asks ESP Screens for them together
(esphome.screen_camera with tiles, size and bg) and the app serves one
BMP, a strip of squares with the corners rounded over each tile's own
colour; every tile draws its square out of it with LVGL's image offset
(LV_IMAGE_ALIGN_TOP_LEFT: the default centres a taller source). A third
online_image on the Guition holds the strip; it loads after the alert's
picture, a cover and the camera full screen, never under a card, in
standby or under a finger. The strip is served whole every time: ESPHome's
http_request logs a 304 as a failed request. Firmware 0.2.77.

Alert button: esp_screens_show_alert takes action and data; the app
performs the action once when the button's report (esphome.screen_alert,
ok) comes from any screen. show_alert keeps its seven fields, so every
firmware from 0.2.31 has it.

Media card and full-page media tile: a title or artist line that is too
wide rolls by (LV_LABEL_LONG_SCROLL_CIRCULAR) instead of ending in dots.

Full-page tiles are white or their own pastel like every other tile; the
tint in the state colour of firmware 0.2.62 to 0.2.76 is gone.

Host harness (27 checks) and bench Guition + local add-on on the Yellow:
docs/TEST_RESULTS_0291.md. CYD firmware 1,633,728 B, 89.0 %.

Co-Authored-By: Claude Fable 5.1 <noreply@anthropic.com>

README_EXTENDED.md

@@ -53,11 +53,9 @@ on the screen itself, and how updates work.
   **presence** (`person.*`). Pick them in the library like any other tile, or
   drag them straight into the screen mockup; **Double-width** is an option for every tile, and so is
   **Full page** (firmware 0.2.62+; not for a Go to page tile): the tile takes the whole page and is
-  one big button that lights up in its state colour while on, so a screen by the door switches the
-  light when you push anywhere on it.
-  Only something that can be off lights up: a light, switch, airco, fan, blind, speaker, robot, script,
-  timer, camera, person or binary sensor. Sensors, numbers, selects, scenes, the weather and the sun stay plain
-  (firmware 0.2.71+).
+  one big button, so a screen by the door switches the light when you push anywhere on it. It is white
+  or its own pastel like every other tile, and its icon shows the state (firmware 0.2.77+; before that
+  the whole tile took its state colour while on).
   Its small slider, direct controls or graph sit at the bottom of the page. A **Go to page** tile
   (`screen.page_1` to `screen.page_8`) opens another page: a full-page light switch on page 1, a menu on page 2.
   Under **Goes to page** the editor offers the pages the screen has and the next, empty one, where a new sub-page
@@ -254,7 +252,8 @@ Home Assistant asks for all seven fields; leave a field empty (`""`, `0`, `false
 don't use it. A new alert replaces the current one. Every end is reported as the event
 **`esphome.screen_alert`** with `action` (`ok`, `timeout`, `replaced`, or `remote`), `title`,
 `screen`, and the `device_id` that Home Assistant adds, so an automation can wait for OK.
-**`esphome.<screen>_dismiss_alert`** clears the card remotely.
+**`esphome.<screen>_dismiss_alert`** clears the card remotely. With the event for every screen, the
+button can also perform a Home Assistant action of your choice (below).
 
 ### All screens at once
 
@@ -307,9 +306,43 @@ actions:
 </p>
 
 A camera or image entity also works as a **tile** on a Guition: a tap opens it full screen, refreshed
-every four seconds. How the image travels (port 8098 of the app, no token on the screen) is in
+every four seconds. From app 0.2.91 with firmware 0.2.77 a camera tile can show a **live picture** in
+the icon's place: in the tile's settings choose **Display → Live picture** and a pace, every 15 or
+30 seconds. The picture is a small square with the tile's rounded corners, the middle of the camera's
+view, and it refreshes while that page is on the screen; a tap still opens the camera full screen. The
+camera tiles of one page share one download, so six live tiles cost the screen no more than one.
+How the image travels (port 8098 of the app, no token on the screen) is in
 [docs/CAMERA.md](docs/CAMERA.md).
 
+### With a button that does something
+
+From app 0.2.91 the event takes an **`action`**: a Home Assistant action the app performs when the
+button is pressed, on whichever screen, once per alert. **`data`** gives the action's fields. The
+screen itself only reports the press (the `esphome.screen_alert` event it always sent), so this works
+with every screen from firmware 0.2.31 and needs no update. A timeout, a new alert over it or
+`esp_screens_dismiss_alert` leaves the action unperformed. The per-screen actions have no `action`
+field.
+
+```yaml
+actions:
+  - event: esp_screens_show_alert
+    event_data:
+      title: "Someone is at the gate"
+      subtitle: "Open it?"
+      icon: doorbell
+      button_text: "Open"
+      timeout: 120
+      action: script.open_gate
+  - event: esp_screens_show_alert
+    event_data:
+      title: "Lights are still on downstairs"
+      button_text: "Turn off"
+      action: light.turn_off
+      data:
+        entity_id: light.downstairs
+        transition: 3
+```
+
 ### Ask Claude
 
 Use Claude Code in Home Assistant? **Settings → Claude → Install for Claude Code** writes an