chore: fix all biome lint errors across monorepo

- Fix import ordering (organizeImports) across multiple packages
- Replace forEach with for...of loops (noForEach)
- Replace non-null assertions with fallback values (noNonNullAssertion)
- Add biome-ignore comments for justified noExplicitAny usages
- Remove parameter properties, use explicit class properties (noParameterProperties)
- Fix string concatenation to template literals (useTemplate)
- Fix format issues (CSS, TypeScript)
- Add tailwindDirectives CSS parser config in biome.json
- Replace var with const (noVar)

Result: 0 errors, 12 warnings (all cognitive complexity, acceptable)

packages/workflow-agent-builtin/__tests__/path.test.ts

@@ -1,6 +1,6 @@
 import { describe, expect, test } from "bun:test";
-import { resolvePath } from "../src/tools/path.js";
 import { resolve } from "node:path";
+import { resolvePath } from "../src/tools/path.js";
 
 describe("resolvePath", () => {
   test("resolves relative paths against cwd", () => {