feat: navigation on the map

[kingazm]

📄 Pull Request Description

Be sure to add in your .env.development

VITE_GOOGLE_MAPS_API_KEY=<key>

Without the key, changes from this PR will not work.

🧩 What was changed?

This PR adds user-location marking and in-map navigation routing to the map feature.

Main changes:

• Added user geolocation handling on the map page (available / outside-campus / unavailable states).
• Added a “show where I am” action in the map header.
• Added route rendering from user location to selected facility using Google Maps directions.
• Added a navigate action in the facility modal (disabled when routing is not possible (no location or user outside campus bounds).

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💡 Why was it changed?

The changes address a nice-to-have feature from our MLP.

The previous map allowed users to view facilities but not easily answer:

• “Where am I?”
• “How do I get there from my current position?”

This change improves UX by:

• giving clear location, with state feedback,
• enabling direct route preview to a selected destination,

It was needed now to make the map actionable (not only browseable) and align with core way-finding expectations.

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⚙️ How was it implemented?

• Added browser geolocation tracking in map logic to maintain current user position.
• Integrated Google Maps DirectionsService + DirectionsRenderer to calculate and draw walking routes.
• Added back navigate button, now with actual functionality.

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⚠️ Side Effects or Risks

• Feature depends on Google Maps key + enabled APIs + billing; without that, routing fails.
• Geolocation permission denial or browser restrictions reduce functionality (but this is handled in the PR).
• Campus-bound logic depends on current bounds strategy and may require tuning for edge locations in the future.

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✅ Checklist

• All 4 sections above are clearly filled out
• Tests and documentation updated (N/A, tested manually)