feat(settings): Settings1 стаб + атомарный стор + seed дефолтов

Store (load_or_seed/get/set/reset/list, durable-write) + SettingsService #[interface] + bin.
v0: строковые значения (variant на проводе), сам сеет дефолты.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
Signed-off-by: Alexander <akotenev2003@gmail.com>

crates/core/shturman-settings/Cargo.toml

@@ -0,0 +1,18 @@
+[package]
+name = "shturman-settings"
+version = "0.0.0"
+edition.workspace = true
+license.workspace = true
+
+[dependencies]
+shturman-ipc = { path = "../../shturman-ipc" }
+shturman-common = { path = "../../shturman-common" }
+zbus.workspace = true
+tokio.workspace = true
+serde_json.workspace = true
+anyhow.workspace = true
+tracing.workspace = true
+
+[dev-dependencies]
+tempfile.workspace = true
+shturman-sdk = { path = "../../shturman-sdk" }