Fit the map to the region and keep attribution clear of the gesture bar

Running the app on an emulator for the first time showed two problems that the
unit tests could not have caught, because both are about what the pixels
actually do.

The configured initial zoom of 7.2 puts the viewport entirely inside the
region on a 411dp-wide screen, so the map rendered as a flat expanse of fill
colour with no outline, border or reference point anywhere in view — it read as
a failure to load. A single zoom number cannot frame a region on both a phone
and a tablet, so the camera now fits the region bounds once the map is ready,
which is correct at any screen size. The configured zoom stays as the starting
position before the fit.

The attribution bar sat behind the system gesture pill. A credit that is
covered by the navigation bar is a credit that is not being displayed, which is
the thing ODbL and CC BY-SA actually require, so it now sits inside a SafeArea.

Also records how to run and screenshot the app on the `nuvolari` AVD, and notes
the pre-existing broken `pixel_7_-_api_35` AVD that is holding 4.8 GB.

Verified on the emulator: the region outline is framed with margin, the
attribution bar is clear of the pill, and the Sources screen shows the
disclaimer, all four credits with their licences, the "no licence stated" line
for ARPA and the share-alike note.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>

Nuvolari/docs/roadmap.md

@@ -54,10 +54,11 @@ network. The attribution bar lists only the sources actually rendered — credit
 OpenStreetMap while showing the fallback would be a false attribution — and sits below
 the map rather than floating over it so no map control can occlude it.
 
-**Not visually verified.** This machine has no Android device and no emulator image, so
-the map has been proven to build and its logic unit-tested, but nobody has watched it
-render. Connect a phone over USB or install an emulator system image before trusting
-the visual result.
+**Verified on an emulator** (`nuvolari`, API 36.1, x86_64, GPU host). Running it caught
+two things the unit tests could not: the configured initial zoom put the viewport
+entirely inside the region so the map read as a blank expanse, and the attribution bar
+sat behind the system gesture pill. Both fixed — the camera now fits the region bounds
+at runtime, which works on any screen size, and the bar is inside a SafeArea.
 
 ## M3 — Animation and timeline 🔨
 
@@ -130,3 +131,32 @@ draft, store listing copy, Data safety draft, prominent disclosure for location.
 | M6 | Firebase project and `google-services.json` |
 | M8 | VPS / object storage endpoint and credentials |
 | M9 | Play Console account and upload keystore |
+
+---
+
+## Verifying on the emulator
+
+An AVD named `nuvolari` is set up on this machine: API 36.1, `google_apis`, x86_64,
+GPU passthrough to the host. It uses a 2 GB data partition and no SD card because disk
+is tight.
+
+```bash
+# Boot it
+"$ANDROID_HOME/emulator/emulator" -avd nuvolari -no-audio -no-boot-anim -gpu host
+
+# Build, install, launch
+cd app
+flutter build apk --debug
+adb install -r build/app/outputs/flutter-apk/app-debug.apk
+adb shell am start -n it.nuvolari.app/.MainActivity
+
+# Capture what it looks like
+adb exec-out screencap -p > screen.png
+```
+
+`flutter run -d emulator-5554` works too and gives hot reload; the steps above are what
+a non-interactive session uses.
+
+> An unrelated AVD, `pixel_7_-_api_35`, is present but broken — its system image
+> (`android-35/google_apis_playstore`) is not installed, so it cannot boot. It occupies
+> about 4.8 GB. It predates this project and has been left alone.