rename: the desktop is Inkwell — crates, Tauri identity, data move, packaging

Step 3 of milestone 481 (Scribe note 5071: a full rename).

- crates thoughtsync-{core,desktop,ffi,uniffi-bindgen} → inkwell-*, the
  Cargo.lock entries moved to match (checked with `cargo metadata --locked`)
- Tauri: productName "Inkwell", identifier com.fabledsword.inkwell, binary
  `inkwell`, updater feed on bvandeusen/inkwell, store file inkwell.db
- client agent inkwell-desktop, headers X-Inkwell-Client/-Protocol (the server
  reads neither), capture event inkwell://captured, display-version env
- .deb: conflicts + replaces thought-sync, so the updater's install retires the
  old package instead of colliding on it. kebab-case("Inkwell") is `inkwell`, so
  the package name finally matches the command and verify.sh now asserts it
- pacman: inkwell, conflicting with and replacing thoughtsync and
  thoughtsync-desktop
- AppImage ~/Applications/Inkwell.AppImage, menu entry inkwell.desktop,
  installer, release titles, desktop asset names in fetch-clients.sh

The one shim, chosen by the operator because it is the only copy of a
local-first user's notes: crossover.rs moves the old
com.fabledsword.thoughtsync app-data dir's contents into the new one on startup,
before the store opens, renaming thoughtsync.db and its -wal/-shm with it. It
skips when the new dir already has a store, and anything already in the new dir
wins (the installer writes its channel marker there first). Tested.

Android's Kotlin side (package, applicationId, uniffi class) is step 4. Its
release asset names stay thoughtsync.* until then.

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

android/app/build.gradle.kts

@@ -16,7 +16,7 @@ val workspaceRoot: Directory = layout.projectDirectory.dir("../..")
 val androidAbis = listOf("arm64-v8a", "armeabi-v7a", "x86", "x86_64")
 
 /**
- * Cross-compile `thoughtsync-ffi` for each Android ABI and drop the resulting
+ * Cross-compile `inkwell-ffi` for each Android ABI and drop the resulting
  * `.so` into jniLibs, where AGP packages it.
  *
  * `ExecOperations` injected rather than `project.exec`: the latter was REMOVED in
@@ -49,7 +49,7 @@ abstract class CargoNdkBuild : DefaultTask() {
             args += "-t"
             args += abi
         }
-        args += listOf("-o", jniLibsDir.get().asFile.absolutePath, "build", "-p", "thoughtsync-ffi")
+        args += listOf("-o", jniLibsDir.get().asFile.absolutePath, "build", "-p", "inkwell-ffi")
         // --locked so an Android build cannot silently re-resolve the workspace
         // lockfile the desktop lanes are gated on.
         args += "--locked"
@@ -94,7 +94,7 @@ abstract class UniffiBindgen : DefaultTask() {
                 "run",
                 "--locked",
                 "-p",
-                "thoughtsync-uniffi-bindgen",
+                "inkwell-uniffi-bindgen",
                 "--",
                 "generate",
                 "--library",
@@ -149,7 +149,7 @@ val bindingsOut = layout.buildDirectory.dir("generated/uniffi")
 
 val cargoNdk =
     tasks.register<CargoNdkBuild>("cargoNdk") {
-        description = "Cross-compile thoughtsync-ffi for the Android ABIs."
+        description = "Cross-compile inkwell-ffi for the Android ABIs."
         rustSources.from(rustInputs)
         abis.set(androidAbis)
         cargoProfile.set(rustProfile)
@@ -163,7 +163,7 @@ val generateBindings =
         dependsOn(cargoNdk)
         // arm64 is arbitrary — every ABI carries the same uniffi metadata, and
         // reading one is cheaper than reading four.
-        libraryFile.set(jniLibsOut.map { it.file("arm64-v8a/libthoughtsync_ffi.so") })
+        libraryFile.set(jniLibsOut.map { it.file("arm64-v8a/libinkwell_ffi.so") })
         workspaceDir.set(workspaceRoot)
         outputDir.set(bindingsOut)
     }