docs: add screenshots and fix stale basalt references in README

Four representative screenshots (Pebble Round 2 menu, countdown, history;
Pebble Time countdown) showing v1.0.0 UI. Also updated the workflow
command list to reflect gabbro as the primary emulator target.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

5 files changed, 10 insertions, 3 deletions

diff --git a/README.md b/README.md
index 23d4f13..3462bff 100644
--- a/README.md
+++ b/README.md
@@ -2,6 +2,12 @@
 
 FastForge is a Pebble watchapp for intermittent fasting tracking, built with the Rebble SDK.
 
+## Screenshots
+
+| Pebble Round 2 — Menu | Pebble Round 2 — Countdown | Pebble Round 2 — History | Pebble Time — Countdown |
+|:---:|:---:|:---:|:---:|
+| ![Menu](screenshots/gabbro_01_menu.png) | ![Countdown](screenshots/gabbro_02_countdown.png) | ![History](screenshots/gabbro_03_history.png) | ![Basalt countdown](screenshots/basalt_01_countdown.png) |
+
 ## Day-1 Setup (Fedora + Rebble SDK 4.9+)
 
 ```bash
@@ -38,8 +44,9 @@ just logs
 Useful commands:
 
 - `just`: list commands
-- `just dev`: build + install to basalt emulator
-- `just logs`: live logs from basalt emulator
-- `just screenshot`: screenshot from basalt emulator
+- `just dev`: build + install to Pebble Round 2 (gabbro) emulator
+- `just dev-basalt`: build + install to Pebble Time (basalt) emulator
+- `just logs`: live logs from gabbro emulator
+- `just screenshot`: screenshot from gabbro emulator
 - `just kill`: stop emulator
 - `just clean`: remove build artifacts
diff --git a/screenshots/basalt_01_countdown.png b/screenshots/basalt_01_countdown.png
new file mode 100644
index 0000000..8c1956f
--- /dev/null
+++ b/screenshots/basalt_01_countdown.png
diff --git a/screenshots/gabbro_01_menu.png b/screenshots/gabbro_01_menu.png
new file mode 100644
index 0000000..08f1cb6
--- /dev/null
+++ b/screenshots/gabbro_01_menu.png
diff --git a/screenshots/gabbro_02_countdown.png b/screenshots/gabbro_02_countdown.png
new file mode 100644
index 0000000..703c3ae
--- /dev/null
+++ b/screenshots/gabbro_02_countdown.png
diff --git a/screenshots/gabbro_03_history.png b/screenshots/gabbro_03_history.png
new file mode 100644
index 0000000..3c82dbd
--- /dev/null
+++ b/screenshots/gabbro_03_history.png