chore: apply cargo fmt across workspace and update docs

- Run cargo fmt on all Rust crates for consistent formatting
- Update CLAUDE.md with WASM plugin commands and dev.ps1 instructions
- Update wiki: add WASM plugin architecture, rewrite dev environment docs
- Minor frontend cleanup (unused imports)

crates/erp-workflow/src/handler/task_handler.rs

@@ -80,7 +80,8 @@ where
     S: Clone + Send + Sync + 'static,
 {
     require_permission(&ctx, "workflow.approve")?;
-    req.validate().map_err(|e| AppError::Validation(e.to_string()))?;
+    req.validate()
+        .map_err(|e| AppError::Validation(e.to_string()))?;
 
     let resp = TaskService::complete(
         id,
@@ -107,10 +108,10 @@ where
     S: Clone + Send + Sync + 'static,
 {
     require_permission(&ctx, "workflow.delegate")?;
-    req.validate().map_err(|e| AppError::Validation(e.to_string()))?;
+    req.validate()
+        .map_err(|e| AppError::Validation(e.to_string()))?;
 
-    let resp =
-        TaskService::delegate(id, ctx.tenant_id, ctx.user_id, &req, &state.db).await?;
+    let resp = TaskService::delegate(id, ctx.tenant_id, ctx.user_id, &req, &state.db).await?;
 
     Ok(Json(ApiResponse::ok(resp)))
 }