Complex geocoding config [MAP-706] [MAP-708] [MAP-707] [MAP-458]

[janbaykara]

This PR adds a new, more capable geocoding option that can involve multiple fields.

• geography_config is a new approach to geocoding. When the field is set (see test cases), it allows three new approaches to geocoding:
  1. Multi-field area geocoding. It can be a single area name, or it could be multiple columns (like council -> ward). A good example of this is the Britain Elects ward-level GE2024 results forecast.
  2. Address geocoding with per-row prefix / suffix / country configurations. A good example of this is a spreadsheet with business names and street names. Both fields are important to get precise coordinates, and adding an arbitrary suffix like "Glasgow" gives the geocoder the context it needs to make the right choices.
  3. Coordinate geocoding. You pick a latitude and longitude field, and the rest is history. This was an explicit request from Tipping Point UK.
• There is a full test suite for these geocoding configurations, and they run on the Github CI test runner as a follow-up step.
• As part of area geocoding, we now import inactive political boundaries from MapIt, taking the row count from 9000~ to over 20,000.
• There are a few cases where we use a new service, findthatpostcode.uk, for backup postcode geocoding when postcodes.io fails.
• When geography_config is set, geocoding cannot be set differently by the user in the UI. So there are some JSX changes for that.

[sentry-io]

🔍 Existing Issues For Review

Your pull request is modifying functions with the following pre-existing issues:

📄 File: hub/management/commands/import_areas.py

Function	Unhandled Issue
handle	BadRequestException: Usage limit reached. utils.m... Event Count: 1

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[linear]

MAP-708 Add "arbitrary location context" geocoding option

MAP-707 Add "use first line" geocoding option

MAP-458 Add latitude / longitude / coordinates geography option and fields