fix: add override keyword to Lit component lifecycle methods

[abalmush]

Add the TypeScript override keyword to all Lit component methods that override parent class methods. This is required for Google's internal repository compilation.

Methods updated:

• render()
• connectedCallback()
• disconnectedCallback()
• firstUpdated()
• willUpdate()

Fixes #463

[gemini-code-assist]

Code Review

This pull request correctly adds the override keyword to Lit component lifecycle methods across multiple files, which is a great improvement for code clarity and to satisfy compiler requirements. My review focuses on a related improvement: adding explicit return types to these same lifecycle methods. Many methods like render, firstUpdated, and willUpdate are missing explicit return types, and adding them would further enhance type safety and maintainability. I've added several suggestions for render and firstUpdated methods. The same principle applies to the multi-line willUpdate signatures, which should also be updated to include a : void return type.

[gemini-code-assist]

To improve type safety and code clarity, it's best practice to explicitly define the return type for component lifecycle methods. The render method returns an HTMLTemplateResult, so that should be its explicit return type. You may need to add HTMLTemplateResult to the imports from lit.

Suggested change

	override render() {
	override render(): HTMLTemplateResult {

[gemini-code-assist]

To improve type safety and code clarity, it's best practice to explicitly define the return type for component lifecycle methods. The render method returns an HTMLTemplateResult, so that should be its explicit return type. You may need to add HTMLTemplateResult to the imports from lit.

Suggested change

	override render() {
	override render(): HTMLTemplateResult {

[gemini-code-assist]

To improve type safety and code clarity, it's best practice to explicitly define the return type for component lifecycle methods. The firstUpdated method should have a void return type.

Suggested change

	override firstUpdated() {
	override firstUpdated(): void {

[gemini-code-assist]

To improve type safety and code clarity, it's best practice to explicitly define the return type for component lifecycle methods. The render method returns an HTMLTemplateResult, so that should be its explicit return type. You may need to add HTMLTemplateResult to the imports from lit.

Suggested change

	override render() {
	override render(): HTMLTemplateResult {

[gemini-code-assist]

To improve type safety and code clarity, it's best practice to explicitly define the return type for component lifecycle methods. The firstUpdated method should have a void return type.

Suggested change

	override firstUpdated() {
	override firstUpdated(): void {

[gemini-code-assist]

To improve type safety and code clarity, it's best practice to explicitly define the return type for component lifecycle methods. The render method returns an HTMLTemplateResult, so that should be its explicit return type. You may need to add HTMLTemplateResult to the imports from lit.

Suggested change

	override render() {
	override render(): HTMLTemplateResult {