fix(customers): default a Place location so signup with a place works

[roncodes]

The bug

POST /v1/customers accepts an optional place object, and the payload documented in the Postman collection sends one. Creating it always failed:

SQLSTATE[HY000]: General error: 1364
Field 'location' doesn't have a default value

places.location is a POINT NOT NULL column with no database default, and the attribute allow-list in resolveCustomerPlace is address-only — a caller cannot supply coordinates through this surface — so Place::create() was always called without one.

Every documented signup that included a place returned a 500.

The fix

Default it to Point(0, 0) — the same placeholder the geocoding helpers already fall back to when an address cannot be resolved (Place::getGoogleAddressArray, Place::findExistingSharedPlace).

The default sits in the base array of the array_merge, and location is not in the allow-list, so a caller can never override it.

Verified against a live stack

• Before: the documented Create a Customer payload → 500 with the error above.
• After: 200, with the address resolved (HOME - 123 MAIN STREET, KINGSTON, 00000, JAMAICA).
• Control: Place::create() without a location still fails with 1364, confirming the default is what fixes it — and the same request with no place key already returned 200 both before and after.

Context

Found while making the Customers folder of the Postman collection pass (fleetbase/fleetbase#581) — this was the last blocker before all 16 requests returned 2xx.

🤖 Generated with Claude Code

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 100.00%. Comparing base (fa37e78) to head (faf20a3).

Additional details and impacted files

@@             Coverage Diff             @@
##                main      #293   +/-   ##
===========================================
  Coverage     100.00%   100.00%           
  Complexity      9766      9766           
===========================================
  Files            521       521           
  Lines          37762     37763    +1     
===========================================
+ Hits           37762     37763    +1     

Flag	Coverage Δ
backend	100.00% <100.00%> (ø)

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