docs(#359): restructure 1.2.0 release notes per Ben's review

Reordered + marketed per direction: platforms-first (Android/Windows/
Linux/Web now shipped every release), then the interface redesign as the
headline (left rail, pinned rail, in-place channel nav), storage, GIFs
(cross-client tap-to-view + Tenor render), a big FEM/LNA callout, deeper
diagnostics (persisted rxTime, honest path units), and performance.

Added <!-- SCREENSHOT: ... --> placeholders at the hero, pinned-rail,
and FEM-LNA spots for Ben to drop captures into the GitHub release
editor (real screenshots must be captured from the running app; not
faking them).

No em-dashes.

Part of #160. Agent: SapphireCompass (session 8d755b5e)

release-notes/1.2.0.md

@@ -1,44 +1,101 @@
 ## Offband Meshcore 1.2.0
 
-A big one. This release rebuilds how Offband stores your data, gives the app a
-new navigation shell, and makes GIFs work across every MeshCore client. It is
-also the first Offband release built, signed, and published across all platforms
-automatically through CI.
+Our biggest release yet. A ground-up interface redesign, a real database under the
+hood, GIFs that work across every MeshCore client, and hands-on control of your
+radio's RF front end. This is also the first Offband release built, signed, and
+shipped to every platform automatically.
 
-### Your data now lives in a real database
+<!-- SCREENSHOT: hero shot of the redesigned app (pinned left rail + a channel open) -->
 
-Messages, contacts, channels, and the rest have moved from scattered preference
-entries to a proper drift / SQLite database. **Your existing data is migrated
-automatically the first time you open this version, and nothing is thrown away.**
-Message history is kept in full, storage errors no longer fail silently, and on
-desktop the database no longer gets tangled up in OneDrive/Documents sync.
+### One app, every platform
 
-Because this is a one-time on-device migration, it is worth backing up nothing in
-particular but simply being aware that the first launch does a little more work
-than usual.
+From this release on, every Offband build ships everywhere at once, signed with
+the same key so updates just work:
 
-### A new way to get around
+- **Android**: install from Google Play or sideload the signed APK
+- **Windows**: desktop build
+- **Linux**: desktop build
+- **Web**: run it right in your browser, no install, at offband.app
 
-There is a new navigation drawer you open from the hamburger button, and you can
-pin it open so it stays alongside your chat. The channel list lives there and you
-can switch channels without leaving the one you are in. Map layer toggles moved
-into the panel, Disconnect and Settings moved to its footer, and Contacts gained
-a filter rail. The back button now behaves the way you would expect: it
-backgrounds the app instead of killing it, and it no longer knocks you off a
-connected radio.
+Pick your platform below.
 
-### GIFs that work everywhere
+### A brand-new interface
 
-GIFs are now sent as a plain Giphy link instead of an Offband-only code, so
-people on other MeshCore clients can actually see them. Pasted Giphy and Tenor
-links render inline, behind a trusted-host allowlist.
+The headline feature. Offband has been rebuilt around a modern navigation shell
+that finally gets out of your way.
 
-### Also in this release
+- A **left rail** you open from the hamburger button, and can **pin open** so it
+  lives right alongside your conversation instead of covering it.
+- Your **channels live in the rail** and switch **in place**, so jumping between
+  channels never loses your spot or your scroll position.
+- Map layer toggles, Disconnect, and Settings all found sensible new homes in the
+  panel, and the back button finally behaves the way it should: it backgrounds
+  the app instead of killing it, and never knocks you off a connected radio.
 
-- Desktop remembers your window position and size.
+<!-- SCREENSHOT: left rail pinned open, showing the channel list -->
+
+### Your data, on solid ground
+
+Under the surface, Offband now keeps your messages, contacts, and channels in a
+real SQLite database instead of a pile of loose preference files.
+
+- Your **existing data migrates automatically** the first time you open this
+  version. Nothing is thrown away, and your **full message history is preserved**.
+- Storage problems that used to fail silently now surface, so nothing goes wrong
+  in the dark.
+- On desktop, your data no longer gets swept into OneDrive/Documents sync.
+
+### GIFs everyone can see
+
+GIFs are no longer an Offband-only party trick.
+
+- Send a GIF and it goes out as a **plain Giphy link**, so people on **stock
+  MeshCore and other clients can tap it and watch it** too, not just Offband
+  users.
+- Paste a **Giphy or Tenor** link and it renders inline, behind a trusted-host
+  safety allowlist.
+
+### Take command of your radio's front end
+
+Power users, this one's for you. On supported hardware, Offband now gives you
+direct control of your radio's **FEM / LNA** (the front-end module and low-noise
+amplifier that shape receive sensitivity and transmit path).
+
+- Toggle **FEM LNA** right from Radio Settings.
+- Device Info now reads out your radio's Offband capabilities, so you can see at a
+  glance what your hardware supports.
+
+Both are gated on firmware capability, so they appear only where the radio
+actually supports them.
+
+<!-- SCREENSHOT: Radio Settings showing the FEM LNA toggle -->
+
+### Deeper diagnostics
+
+More signal, less guesswork when you need to see what your mesh is doing.
+
+- Message **arrival time is now logged and persisted** separately from the claimed
+  send time, so you can tell when a message really reached you versus when the
+  sender says it left (#285).
+- Path diagnostics report **honest, width-aware units** instead of mislabeled hop
+  counts, and path lengths decode exactly per the firmware contract.
+
+### Faster across the board
+
+The new storage engine and a round of under-the-hood work add up to a noticeably
+snappier app.
+
+- Connecting no longer rewrites your entire preferences file for every channel, so
+  connect time is quicker and lighter on storage.
+- Bulk reads and writes go through the database now, which scales far better as
+  your message and contact history grows.
+
+### And a few more
+
+- Desktop remembers your window size and position between launches.
 - Reach a contact's settings straight from its long-press menu.
-- FEM LNA control and Offband capability readout in Device Info, where the radio
-  supports it.
 - You can no longer accidentally block your own node.
 
-Full details in the changelog.
+---
+
+See the full, itemized changelog in the repository.