Add hint of reset keyboard shortcut

[Rowrow620]

First Timers Only

This issue is reserved for developers who are new to AlgoBuddy or open-source contributing. We know that submitting a first pull request can feel intimidating. The goal of this issue is to guide you step-by-step through making your first contribution to the AlgoBuddy repository.

Description of the Issue

The timeline control bar displays playback buttons, but users may not realize that pressing R on their keyboard resets the timeline instantly.

Proposed Solution

Add a small keyboard shortcut badge, hover text, or hint to the text label of the Reset button in the control bar.

Implementation Steps

1. Open src/ui/header.rs and locate the Reset button in the playback controls section.
2. Update the button with a tooltip:

   if ui.button("Reset [R]")
       .on_hover_text("Reset timeline to step 1 (Shortcut: R)")
       .clicked()
   {
       app.current_step_idx = 0;
       app.is_playing = false;
   }

3. Test locally using cargo run

Acceptance Criteria

To merge a pull request for this issue:

• Code Formatting: cargo fmt --all -- --check completes without warnings.
• All Tests Pass: cargo test passes 100% of unit tests.
• Issue Solved: The implementation fully addresses the requirements described above.
• Clean Git Branch: Changes are committed to a feature branch targeting dev.

Step-by-Step Contribution Guide

1. Claim this issue: Comment below that you are working on this issue to receive assignment.
2. Fork and Branch: Create a new branch off dev named issue-[id]-[feature-name].
3. Make and Test Changes: Run cargo fmt --all and cargo test locally to verify build health.
4. Submit PR: Push your branch to GitHub and create a Pull Request targeting the dev branch.

Additional Information

• Contributing Guide
• README