🎨 Palette: Add async loading state to authentication buttons

[singhaditya21]

💡 What: Added disabled loading states to the login and register buttons during asynchronous API calls.
🎯 Why: Prevents users from repeatedly clicking the submit button while the request is processing and provides immediate, helpful visual feedback.
📸 Before/After: Visual changes verified via Playwright screenshot where the button turns semi-transparent, disables itself, and shows "Logging in... ⏳".
♿ Accessibility: Improves accessibility by explicitly indicating the disabled processing state and preventing multiple accidental form submissions via keyboard or screen readers.

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PR created automatically by Jules for task 12895610073496265361 started by @singhaditya21

[google-labs-jules]

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[singhaditya21]

Closing as a duplicate. An automated agent opened 144 near-identical PRs adding loading states to the web-demo auth buttons, one per day. Closing the batch to clear the review queue; the branch is retained if this change is still wanted, and the work is small enough to redo in a single focused PR. See ROADMAP.md for the current backlog.

[google-labs-jules]

Closing as a duplicate. An automated agent opened 144 near-identical PRs adding loading states to the web-demo auth buttons, one per day. Closing the batch to clear the review queue; the branch is retained if this change is still wanted, and the work is small enough to redo in a single focused PR. See ROADMAP.md for the current backlog.

Understood. Acknowledging that this work is being closed as a duplicate and stopping work on this task.