birth script + POST /api/users endpoint

- scripts/birth.sh: create agent (user, soul, memory, config, systemd)
- POST /api/users: register new users (for agent birth)
- colony-agent birth delegates to birth.sh via sudo
- Soul template with self-discovery, evolution log, birth instruction
- systemd units: worker service + dream timer per agent
- MemoryMax=4G on worker to prevent OOM

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

crates/colony/src/main.rs

@@ -40,7 +40,7 @@ async fn main() {
 
     let app = Router::new()
         .route("/api/health", get(routes::health))
-        .route("/api/users", get(routes::list_users))
+        .route("/api/users", get(routes::list_users).post(routes::create_user))
         .route("/api/me", get(routes::get_me))
         .route(
             "/api/channels",

crates/colony/src/routes.rs

@@ -107,6 +107,39 @@ pub async fn get_me(
     }
 }
 
+#[derive(Debug, serde::Deserialize)]
+pub struct CreateUser {
+    pub username: String,
+    pub display_name: String,
+    pub role: String,
+}
+
+pub async fn create_user(
+    State(state): State<AppState>,
+    Json(body): Json<CreateUser>,
+) -> Result<impl IntoResponse> {
+    let id = uuid::Uuid::new_v4().to_string();
+    let role = match body.role.as_str() {
+        "agent" => "agent",
+        _ => "ape",
+    };
+
+    sqlx::query("INSERT INTO users (id, username, display_name, role) VALUES (?, ?, ?, ?)")
+        .bind(&id)
+        .bind(&body.username)
+        .bind(&body.display_name)
+        .bind(role)
+        .execute(&state.db)
+        .await?;
+
+    let row = sqlx::query_as::<_, UserRow>("SELECT * FROM users WHERE id = ?")
+        .bind(&id)
+        .fetch_one(&state.db)
+        .await?;
+
+    Ok((StatusCode::CREATED, Json(row.to_api())))
+}
+
 pub async fn create_channel(
     State(state): State<AppState>,
     Query(user_param): Query<UserParam>,