feat(model-server): backend modèles locaux — serveur llama.cpp intégré (#35) et profils OpenCode locaux multiples (#36)

Sprint « Modeles locaux », couche backend (domain/application/infra/app-tauri).

#35 — Serveur de modèle local intégré (llama.cpp) :
- domain: model_server.rs (agrégat + statut), ports ModelServerProbe /
  ManagedProcess / ModelServerRuntime / ModelServerRegistry, événements
  model_server_status_changed et agent_launch_failed.
- application: use case EnsureLocalModelServer branché sur LaunchAgent.
- infrastructure: adapters HttpOpenAiCompatibleProbe, LlamaCppRuntime,
  LocalManagedProcess, FsModelServerRegistry.
- app-tauri: DTO plat LocalModelServerConfigDto, commandes
  list/save/delete_model_server avec garde model_server_in_use, wiring.

#36 — Profils OpenCode locaux multiples :
- domain: VO LocalModelServerId, OpenCodeConfig.local_model_server_id.
- application: use case CloneOpenCodeProfileFromSeed.
- app-tauri: commande clone_opencode_profile_from_seed, DTO/wiring.

Tests verts (exécution réelle) : domain+application OK, app-tauri
dto_model_servers 3/3 et dto_profiles 10/10, infra model_server 2/2,
application model_server+profile_usecases 19/19, cargo build workspace Finished.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

crates/domain/src/ids.rs

@@ -68,6 +68,10 @@ typed_id!(
     /// Identifies an [`crate::profile::AgentProfile`].
     ProfileId
 );
+typed_id!(
+    /// Identifies a local model server configuration.
+    LocalModelServerId
+);
 typed_id!(
     /// Identifies a [`crate::skill::Skill`].
     SkillId