Import bookmarks and identities from the TeamSpeak 3 client

The official client keeps what a myTeamSpeak account synchronises as protobuf
Item_Data blobs in the ProtobufItems table of settings.db. Decode them, adopt
them on first run when we have no identity yet, and offer a re-import from
Manage Bookmarks and Identities. The settings.db reader moves from contacts to
a new teamspeak package.

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

ts3-client/README.md

@@ -76,6 +76,14 @@ frontend supplies its own UI and audio backend while reusing `core` unchanged.
 - **Identity management** (Tools → Identities) — keep several identities, mark one
   as the default, pick one per server or per bookmark, rename, raise an identity's
   security level, and import/export TeamSpeak-compatible `.ini` identity files.
+- **Import from TeamSpeak 3 / myTeamSpeak** — the official client keeps its bookmarks
+  and identities (the data a myTeamSpeak account synchronises) as protobuf
+  `Item_Data` blobs in the `ProtobufItems` table of its `settings.db`. On first run,
+  when this client has no identity of its own yet, it adopts all of them — identities,
+  the default identity and its nickname, and the bookmarks with the identities they
+  connect with; "Import from TeamSpeak 3…" in Manage Bookmarks and in Identities
+  re-imports at any time (additive: known identities and bookmarks are left alone).
+  The schema was recovered from the descriptors embedded in the client binary.
 - **Contacts** (Tools → Contacts) — TeamSpeak's friend/blocked list: mark a client as
   **Friend**, **Blocked** or **Neutral** from its context menu (or drag it into the
   window), give it a custom and a phonetic nickname, choose how the name is shown
@@ -190,6 +198,12 @@ core/   com.ts3client
 ├── config.Settings          persisted prefs (~/.ts3jclient/settings.properties)
 ├── config.Bookmarks         persisted server bookmarks (with per-server identity)
 ├── config.IdentityStore     managed identities (~/.ts3jclient/identities/*.ini)
+├── teamspeak                the official client's own data files
+│   ├── TeamSpeakSettingsDb  locates settings.db; reads Contacts and the ProtobufItems sync store
+│   ├── SqliteReader         minimal read-only SQLite 3 file reader (no driver)
+│   ├── SyncItem             a synced bookmark / identity / folder (Item_Data)
+│   ├── SyncItemDecoder      protobuf wire decoding of Item_Data, via ProtobufReader
+│   └── TeamSpeakImporter    merges synced items into IdentityStore / Bookmarks
 ├── audio                    abstractions + reusable DSP (no platform code)
 │   ├── AudioBackend         factory for a platform's VoiceInput/VoiceOutput
 │   ├── VoiceInput           capture source (extends ts3j Microphone) + gating controls