rename: Android is Inkwell — package, applicationId, uniffi class, assets

Step 4 of milestone 481 (Scribe note 5071: a full rename).

- namespace and applicationId com.fabledsword.inkwell; the Kotlin package moves
  with them, and ktlint re-sorted the imports the rename reordered (checked
  locally with CI's ktlint 1.4.0 and detekt 1.23.7, both clean)
- uniffi: class Inkwell in com.fabledsword.inkwell.core, InkwellApplication,
  InkwellTheme, Theme.Inkwell, log tags, prefs and work names, client agent
  inkwell-android
- the lane publishes inkwell.apk / inkwell-android.json; fetch-clients,
  guard-forward, publish-release and write-manifest read the same names

A new applicationId is a new app. The old ThoughtSync app keeps its own store
and stays installed beside it. Notes cross over by syncing, and the old app is
then removed by hand.

Kept: the signing keyAlias is still "thoughtsync". It names the key inside the
existing keystore, and the key, and so the certificate, are unchanged.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

android/settings.gradle.kts

@@ -18,7 +18,7 @@ dependencyResolutionManagement {
         mavenCentral()
     }
 }
-rootProject.name = "ThoughtSync"
+rootProject.name = "Inkwell"
 
 // `ffi/` sits beside `app/` but is deliberately NOT a Gradle module: it is a Rust
 // crate belonging to the Cargo workspace at the repo root. Gradle reaches it by