rename: the apps say Inkwell — web, desktop, Android and server strings

ThoughtSync is renamed Inkwell ("Fabled Inkwell" in full; Scribe note 5071).
This is step 1 of milestone 481: every string a person reads in the running
apps. Identities installed clients depend on are deliberately untouched — the
Tauri productName (it derives the .deb Package: field), identifier and binary
name, applicationId, X-ThoughtSync-* headers, the export's app marker, env vars,
module and crate names.

- web: title, PWA manifest (name "Fabled Inkwell", short_name "Inkwell"),
  offline page, icon labels, build labels, prompts, notification title
- server: site_name default, import error, link-preview User-Agent
- 0030: a stored site_name of exactly the old default follows the rename. The
  Settings page saves every key, so most servers hold "ThoughtSync" without an
  admin ever having chosen it; a name they typed is left alone
- desktop: window title, default device name, local-mode site name, log line
- android: app_name and the strings that name the app
- core: probe and compatibility messages

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

core/src/sync/client.rs

@@ -1,4 +1,4 @@
-//! HTTP transport to a ThoughtSync server.
+//! HTTP transport to an Inkwell server.
 //!
 //! Covers the compatibility handshake (M10.6) and device-token auth (M10.7a). The
 //! engine that moves notes — push, pull, cursor — grows on top of the same client,
@@ -151,8 +151,8 @@ fn unexpected_status(base_url: &str, status: StatusCode) -> String {
 
 /// Ask a server who it is and whether we can sync with it.
 ///
-/// `Err` means we never got a usable answer (bad address, unreachable, not a
-/// ThoughtSync server). A server that answers but is *incompatible* comes back `Ok`
+/// `Err` means we never got a usable answer (bad address, unreachable, not an
+/// Inkwell server). A server that answers but is *incompatible* comes back `Ok`
 /// with a verdict — that distinction matters, because the two need very different
 /// messages: one is "check what you typed", the other is "update something".
 pub async fn probe(raw_url: &str) -> Result<ProbeResult, String> {
@@ -170,12 +170,12 @@ pub async fn probe(raw_url: &str) -> Result<ProbeResult, String> {
         return Err(unexpected_status(&base_url, status));
     }
 
-    // Something answered 200 that isn't a ThoughtSync server (a router login page, a
+    // Something answered 200 that isn't an Inkwell server (a router login page, a
     // captive portal). Report the address, not the parse error, which would mean
     // nothing to the person reading it.
     let server: ServerInfo = response.json().await.map_err(|_| {
         format!(
-            "{base_url} responded, but not with ThoughtSync's configuration. \
+            "{base_url} responded, but not with Inkwell's configuration. \
              Is that the right address?"
         )
     })?;