fix(runtime): detection non bloquante, bornée dans le temps, HTTP pour les profils locaux (#28)

Le first-run wizard restait figé : `CliAgentRuntime::detect` construisait un
runtime tokio courant-thread via `futures_block_on` pour piloter un
`ProcessSpawner` async. Appelé depuis le runtime async de Tauri, ce
`block_on` imbriqué panique ; la commande IPC ne répond alors jamais, la
promesse `detectProfiles` reste pendante et `busy` ne redescend plus.

Ce commit s'attaque à la cause côté backend :

- `AgentRuntime::detect` devient `async fn` (`#[async_trait]`) : le port cesse
  de mentir sur sa nature. Il pilote un spawner async, il est async. Le
  `futures_block_on` disparaît, et avec lui le runtime imbriqué.
- La sonde CLI est bornée par `tokio::time::timeout(DETECTION_TIMEOUT)` :
  un binaire qui ne rend jamais la main dégrade la détection en `Err`, il
  ne gèle plus l'appelant.
- Les profils `StructuredAdapter::OpenAiCompatible` n'ont pas de CLI à
  spawner : les sonder revenait à tester un binaire inexistant. Ils sont
  désormais sondés par un GET HTTP sur l'endpoint `/models` dérivé de
  `chat_http.endpoint`, borné par le même timeout.

`DetectProfiles` séquence les `await` sur les candidats. Les fakes
`AgentRuntime` des crates application/infrastructure/app-tauri suivent la
nouvelle signature.

Tests: cargo test -p domain (241), -p application (81), -p infrastructure
(269), -p app-tauri (63+15) — verts. `rg futures_block_on crates` sans match.

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

crates/application/tests/agent_lifecycle.rs

@@ -318,8 +318,9 @@ impl FakeRuntime {
     }
 }
 
+#[async_trait]
 impl AgentRuntime for FakeRuntime {
-    fn detect(&self, _profile: &AgentProfile) -> Result<bool, RuntimeError> {
+    async fn detect(&self, _profile: &AgentProfile) -> Result<bool, RuntimeError> {
         Ok(true)
     }
     fn prepare_invocation(

crates/application/tests/change_agent_profile.rs

@@ -344,8 +344,9 @@ impl FakeRuntime {
     }
 }
 
+#[async_trait]
 impl AgentRuntime for FakeRuntime {
-    fn detect(&self, _profile: &AgentProfile) -> Result<bool, RuntimeError> {
+    async fn detect(&self, _profile: &AgentProfile) -> Result<bool, RuntimeError> {
         Ok(true)
     }
     fn prepare_invocation(

crates/application/tests/orchestrator_service.rs

@@ -262,8 +262,9 @@ impl SkillStore for RecordingSkills {
 }
 
 struct FakeRuntime;
+#[async_trait]
 impl AgentRuntime for FakeRuntime {
-    fn detect(&self, _profile: &AgentProfile) -> Result<bool, RuntimeError> {
+    async fn detect(&self, _profile: &AgentProfile) -> Result<bool, RuntimeError> {
         Ok(true)
     }
     fn prepare_invocation(

crates/application/tests/profile_usecases.rs

@@ -86,9 +86,11 @@ struct StubRuntime {
     by_command: HashMap<String, DetectResult>,
 }
 
+struct YieldingRuntime;
+
 #[async_trait]
 impl AgentRuntime for StubRuntime {
-    fn detect(&self, profile: &AgentProfile) -> Result<bool, RuntimeError> {
+    async fn detect(&self, profile: &AgentProfile) -> Result<bool, RuntimeError> {
         match self.by_command.get(&profile.command) {
             Some(DetectResult::Available) => Ok(true),
             Some(DetectResult::Missing) | None => Ok(false),
@@ -107,6 +109,24 @@ impl AgentRuntime for StubRuntime {
     }
 }
 
+#[async_trait]
+impl AgentRuntime for YieldingRuntime {
+    async fn detect(&self, _profile: &AgentProfile) -> Result<bool, RuntimeError> {
+        tokio::task::yield_now().await;
+        Ok(true)
+    }
+
+    fn prepare_invocation(
+        &self,
+        _profile: &AgentProfile,
+        _ctx: &PreparedContext,
+        _cwd: &ProjectPath,
+        _session: &SessionPlan,
+    ) -> Result<SpawnSpec, RuntimeError> {
+        unreachable!("not used in these tests")
+    }
+}
+
 fn profile(id: u128, name: &str, command: &str) -> AgentProfile {
     AgentProfile::new(
         ProfileId::from_uuid(uuid::Uuid::from_u128(id)),
@@ -167,6 +187,20 @@ async fn detect_error_degrades_to_unavailable_not_hard_failure() {
     );
 }
 
+#[tokio::test(flavor = "multi_thread")]
+async fn detect_execute_awaits_async_runtime_without_nested_runtime_panic() {
+    let detect = DetectProfiles::new(Arc::new(YieldingRuntime));
+    let out = detect
+        .execute(DetectProfilesInput {
+            candidates: vec![profile(1, "Claude", "claude")],
+        })
+        .await
+        .expect("async detection must complete inside a multi-thread Tokio runtime");
+
+    assert_eq!(out.results.len(), 1);
+    assert!(out.results[0].available);
+}
+
 // ---------------------------------------------------------------------------
 // ConfigureProfiles
 // ---------------------------------------------------------------------------

crates/application/tests/structured_launch_d3.rs

@@ -284,8 +284,9 @@ impl FakeRuntime {
     }
 }
 
+#[async_trait]
 impl AgentRuntime for FakeRuntime {
-    fn detect(&self, _profile: &AgentProfile) -> Result<bool, RuntimeError> {
+    async fn detect(&self, _profile: &AgentProfile) -> Result<bool, RuntimeError> {
         Ok(true)
     }
     fn prepare_invocation(