feat(saas): industry agent template assignment system

Phase 1-8 of industry-agent-delivery plan:

- DB migration: accounts.assigned_template_id (ON DELETE SET NULL)
- SaaS API: 4 new endpoints (assign/get/unassign/create-agent)
- Service layer: assign_template_to_account, get_assigned_template, unassign_template, create_agent_from_template)
- Types: AssignTemplateRequest, AgentConfigFromTemplate (capabilities merged into tools)
- Frontend SaaS Client: assignTemplate, getAssignedTemplate, unassignTemplate, createAgentFromTemplate
- saasStore: assignedTemplate state + login auto-fetch + actions
- saas-relay-client: fix unused import and saasUrl reference error
- connectionStore: fix relayModel undefined error
- capabilities default to glm-4-flash

- Route registration: new template assignment routes

Cospec and handlers consolidated

Build: cargo check --workspace PASS, tsc --noEmit Pass

crates/zclaw-saas/src/agent_template/service.rs

@@ -266,3 +266,118 @@ pub async fn archive_template(db: &PgPool, id: &str) -> SaasResult<AgentTemplate
     update_template(db, id, None, None, None, None, None, None, None, None, Some("archived"),
                     None, None, None, None, None, None, None).await
 }
+
+// --- Template Assignment ---
+
+/// Assign a template to the current account.
+/// Updates accounts.assigned_template_id and returns the template info.
+pub async fn assign_template_to_account(
+    db: &PgPool,
+    account_id: &str,
+    template_id: &str,
+) -> SaasResult<AgentTemplateInfo> {
+    // Verify template exists and is active
+    let template = get_template(db, template_id).await?;
+    if template.status != "active" {
+        return Err(SaasError::InvalidInput("模板不可用（已归档）".into()));
+    }
+
+    let now = chrono::Utc::now().to_rfc3339();
+    sqlx::query(
+        "UPDATE accounts SET assigned_template_id = $1, updated_at = $2 WHERE id = $3"
+    )
+    .bind(template_id)
+    .bind(&now)
+    .bind(account_id)
+    .execute(db)
+    .await?;
+
+    Ok(template)
+}
+
+/// Get the template assigned to the current account (if any).
+pub async fn get_assigned_template(
+    db: &PgPool,
+    account_id: &str,
+) -> SaasResult<Option<AgentTemplateInfo>> {
+    let row = sqlx::query_scalar::<_, Option<String>>(
+        "SELECT assigned_template_id FROM accounts WHERE id = $1"
+    )
+    .bind(account_id)
+    .fetch_optional(db)
+    .await?;
+
+    let template_id = match row.flatten() {
+        Some(id) => id,
+        None => return Ok(None),
+    };
+
+    // Template may have been deleted (ON DELETE SET NULL), but check anyway
+    match get_template(db, &template_id).await {
+        Ok(t) => Ok(Some(t)),
+        Err(SaasError::NotFound(_)) => {
+            // Template deleted — clear stale reference
+            let now = chrono::Utc::now().to_rfc3339();
+            sqlx::query(
+                "UPDATE accounts SET assigned_template_id = NULL, updated_at = $1 WHERE id = $2"
+            )
+            .bind(&now)
+            .bind(account_id)
+            .execute(db)
+            .await?;
+            Ok(None)
+        }
+        Err(e) => Err(e),
+    }
+}
+
+/// Unassign template from the current account.
+pub async fn unassign_template(
+    db: &PgPool,
+    account_id: &str,
+) -> SaasResult<()> {
+    let now = chrono::Utc::now().to_rfc3339();
+    sqlx::query(
+        "UPDATE accounts SET assigned_template_id = NULL, updated_at = $1 WHERE id = $2"
+    )
+    .bind(&now)
+    .bind(account_id)
+    .execute(db)
+    .await?;
+    Ok(())
+}
+
+/// Create an agent configuration from a template.
+/// Merges capabilities into tools, applies default model fallback.
+pub async fn create_agent_from_template(
+    db: &PgPool,
+    template_id: &str,
+) -> SaasResult<AgentConfigFromTemplate> {
+    let t = get_template(db, template_id).await?;
+    if t.status != "active" {
+        return Err(SaasError::InvalidInput("模板不可用（已归档）".into()));
+    }
+
+    // Merge capabilities into tools (deduplicated)
+    let mut merged_tools = t.tools.clone();
+    for cap in &t.capabilities {
+        if !merged_tools.contains(cap) {
+            merged_tools.push(cap.clone());
+        }
+    }
+
+    Ok(AgentConfigFromTemplate {
+        name: t.name,
+        model: t.model.unwrap_or_else(|| "glm-4-flash".to_string()),
+        system_prompt: t.system_prompt,
+        tools: merged_tools,
+        soul_content: t.soul_content,
+        welcome_message: t.welcome_message,
+        quick_commands: t.quick_commands,
+        temperature: t.temperature,
+        max_tokens: t.max_tokens,
+        personality: t.personality,
+        communication_style: t.communication_style,
+        emoji: t.emoji,
+    })
+}