chore(release): promote to 1.0.0 stable [version set]

The app is stable, so mark this as the 1.0.0 milestone. The CI bump step
now honors a [version set] marker: when present it ships the pinned semver
as-is and only advances the build number (Play requires it monotonic),
instead of the automatic patch bump that cannot cross the 0.x -> 1.0.0
boundary. Normal commits keep auto-incrementing the patch (1.0.1, 1.0.2, ...).

pubspec.yaml

@@ -1,7 +1,7 @@
 name: pluriwave
 description: "Radio mundial con ecualizador, reconocimiento de canciones y UI premium"
 publish_to: 'none'
-version: 0.1.102+103
+version: 1.0.0+103
 
 environment:
   sdk: ^3.7.0