feat(cross-project): découverte et contact inter-projets — tools MCP idea_project_{list,read_context,list_agents,ask_agent,cancel_agent}, permission contactable par agent + default_contactable persistée dans les templates, routage orchestrator par projectId+agentId — #260 (tests ciblés verts, QA en attente)

crates/domain/src/template.rs

@@ -74,6 +74,9 @@ pub struct AgentTemplate {
         skip_serializing_if = "Option::is_none"
     )]
     pub default_mcp_tool_policy: Option<McpToolPolicy>,
+    /// Whether agents created from this template are cross-project contactable.
+    #[serde(default, skip_serializing_if = "std::ops::Not::not")]
+    pub default_contactable: bool,
 }
 
 impl AgentTemplate {
@@ -98,6 +101,7 @@ impl AgentTemplate {
             default_agent_name: None,
             default_system_permissions: None,
             default_mcp_tool_policy: None,
+            default_contactable: false,
         })
     }
 
@@ -125,6 +129,7 @@ impl AgentTemplate {
         default_agent_name: Option<String>,
         default_system_permissions: Option<SystemPermissionSet>,
         default_mcp_tool_policy: Option<McpToolPolicy>,
+        default_contactable: bool,
     ) -> Result<Self, DomainError> {
         crate::validation::non_empty(&name, "template.name")?;
         if let Some(default_agent_name) = &default_agent_name {
@@ -136,6 +141,7 @@ impl AgentTemplate {
             default_agent_name,
             default_system_permissions,
             default_mcp_tool_policy,
+            default_contactable,
             ..self.clone()
         })
     }