feat(edit): conflict dialog on save + store metadata refresh (v2.0)

No locking (plan 03, decision 5): openForEdit keeps an EditSnapshot — the
prefilled form plus the raw Events-row times, which the form itself can't
see (it derives its times from the tapped occurrence, so an externally
moved event would otherwise stay invisible). Right before writing,
performSave re-reads the event and compares snapshots: a mismatch parks
the save in SaveUiState.AwaitingConflict carrying the already-chosen
recurring scope, and the dialog offers overwrite / discard / cancel
(OptionCard style). Overwrite still writes only dirty fields, so external
changes to untouched fields survive either way. A deleted event lands in
SaveUiState.Gone — an informational dialog that closes form and detail.
Fields the form can't write (attendees, status, self response, reminder
methods) are excluded from the comparison so sync noise can't fake a
conflict. The load-time zone is pinned in the EditTarget so a device
timezone change mid-edit can't either.

Store metadata: F-Droid descriptions (DE+EN) and the README stop claiming
read-only and now describe write support and reminder delivery. New
fastlane phoneScreenshots (6 per locale: week/month/day/detail/form/
reminder onboarding), captured on-device against demo-only calendars.

Tests: EditSnapshot equality (unchanged event, field change, row-time move
the form can't see, non-writable changes stay quiet).

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

fdroid-metadata/de.jeanlucmakiola.calendula/en-US/description.txt

@@ -1,11 +1,15 @@
-Calendula is a modern, open-source calendar app for Android. It reads from
-the system calendar provider, so any source synced to your device — Nextcloud
-via DAVx5, Google, local, WebCal subscriptions — shows up automatically.
+Calendula is a modern, open-source calendar app for Android. It works
+directly on the system calendar provider, so any source synced to your
+device — Nextcloud via DAVx5, Google, local, WebCal subscriptions — shows up
+automatically, and changes you make sync back the same way.
 
-The differentiator is the design: real Material 3 Expressive throughout, with
-dynamic color, expressive motion, and expressive shapes.
+Create, edit and delete events, including recurring events with scoped
+changes (only this event / this and all following / the whole series) and a
+simple repeat picker. Calendula also delivers your event reminders as
+notifications — tap one and you're on the event.
 
-V1 is read-only. Event creation, editing, and deletion are planned for V2.
+The differentiator is the design: real Material 3 Expressive throughout,
+with dynamic color, expressive motion, and expressive shapes.
 
 Privacy: zero telemetry, no analytics, no network access — your data never
 leaves the device.