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/infrastructure/src/lib.rs

@@ -26,6 +26,7 @@ pub mod input;
 pub mod inspector;
 pub mod issues;
 pub mod mailbox;
+pub mod model_server;
 pub mod orchestrator;
 pub mod permission;
 pub mod process;
@@ -64,6 +65,9 @@ pub use inspector::{
 };
 pub use issues::{FsIssueNumberAllocator, FsIssueStore};
 pub use mailbox::InMemoryMailbox;
+pub use model_server::{
+    FsModelServerRegistry, HttpOpenAiCompatibleProbe, LlamaCppRuntime, LocalManagedProcess,
+};
 pub use orchestrator::mcp::{
     McpServer, MemoryTransport, StdioTransport, TicketToolError, TicketToolProvider,
     ToolPolicyRegistry,