feat: add GPX download for takeoff point in waypoint popup

[srahim457]

What type of PR is this? (check all applicable)

• 🍕 Feature
• 🐛 Bug Fix
• 📝 Documentation
• 🧑‍💻 Refactor
• ✅ Test
• 🤖 Build or CI
• ❓ Other (please specify)

Related Issue

Fixes #848

Describe this PR

I added a download button that sits next to the copy button on the coordinate popup for the starting waypoint.
It downloads the coordinates of the starting waypoint as a GPX file. The changes were made in MapSection.tsx and I made changes to the message keys in en.json for the tooltip and toast alert.

AI Tool Usage

• No AI tools were used
• AI tools were used (complete below)

If AI-assisted:

• Tool(s) used: Claude (web version, not Claude Code)
• What was generated: I mainly used it to navigate the codebase. It generated the snippets for the download button.
• What you reviewed and changed: I reviewed the code, all the changes were put in by me. Changes in the en.json for the messages and the actual button, styling and download function in MapSection.tsx

Screenshots

before:

after:

Alternative Approaches Considered

Not really, refer to #848 thread for thought process.

Review Guide

I tested it manually.
I made a project, then I logged in as Drone Operator, locked a task and then when I opened the task I clicked on the starting point pin to see the popup. I downloaded the GPX file, tested it using an online GPX viewer and just opening the file in a text editor to check if the longitude and latitude are correct.

Checklist

• I have read the Contributing Guide
• I have read the Code of Conduct
• PR is focused and small
• Tests are included or updated (I haven't made any tests)
• I understand all code in this PR and can answer questions about it
• No secrets, credentials, or sensitive data are included
• Commit messages are descriptive
• Related docs and screenshots are updated (I don't know where I update these ?)

[optional] What gif best describes this PR or how it makes you feel?

[github-actions]

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[srahim457]

I have read the CONTRIBUTING.md document and I hereby sign and agree with the guidelines

[spwoodcock]

Good stuff, thanks!