Fix ProjectUserDict usage and standardise geojson parsing/usage throughout

[spwoodcock]

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

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

Related Issue

Related to #1657

Describe this PR

• Fixes issue where we no longer use AuthUser for the mapper endpoints, but instead a dict ProjectUserDict, where the DbUser and DbProject must be obtained from keys user and project respectively.
• I also refactored the project_crud and project_routes logic to take this into account and be more efficient (preventing double db access to get the project twice, as we now have it available).
• TODO also need to update the logic / fix for task_routes and submission_routes. @Sujanadh please pick up where I left off 🙏
• I also took the opportunity to do a big refactor of our geojson handling, as it started to spraw a bit.
  • I tried to reuse the same functions as much as possible, handling the geojson as FeatureCollection where possible.
  • I also separated usage of jazzband/geojson and geojson_pydantic: geojson_pydantic is used for the pydantic models only, then all other usage defers to .geojson.
  • Please test endpoints thoroughly after the refactor 😄
  • The endpoints I updated are working & project creation / viewing also seems to work fine for me.

@Sujanadh the remaining task:

• Replace current_user: AuthUser = Depends(mapper) with project_user: ProjectUserDict = Depends(mapper) in submission_routes and task_routes.
• In all cases where this is replaced, ensure the logic uses .get("project") if required
• If the project is got via another function, try to remove that logic and refer to project_user.get("project") where possible.

Review Guide

Test the things!

Checklist before requesting a review

• 📖 Read the FMTM Contributing Guide: https://github.com/hotosm/fmtm/blob/main/CONTRIBUTING.md
• 📖 Read the HOT Code of Conduct: https://docs.hotosm.org/code-of-conduct
• 👷‍♀️ Create small PRs. In most cases, this will be possible.
• ✅ Provide tests for your changes.
• 📝 Use descriptive commit messages.
• 📗 Update any related documentation and include any relevant screenshots.

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[Sujanadh]

Thats a huge refactor 🙌

[Sujanadh]

looks all good I tried creating project, made submissions, filter, review status, update entity status all seems working pretty good 👍

[Sujanadh]

I added back your code from your last commit to better handle invalid multipolygon geoms which was removed when merging conflicts.