feat: Expose source of stand assignment in API

[MrAdder]

Fixes #1745

🧾 Summary of changes (Expose “reservation allocator” source on stand assignments)

🔎 API responses now indicate if an assignment came from the reservation allocator

• Updates StandController responses to include a new boolean:
  • ✅ assigned_by_reservation_allocator

This flag is set by checking the latest assignment history record and detecting whether the type starts with:

• App\\Allocator\\Stand\\UserRequestedArrivalStandAllocator

---

🚚 GET /stand/assignment (all assignments)

• Now eager-loads assignment history:
  • StandAssignment::with('assignmentHistory')->get()
• Each returned assignment includes:
  • callsign
  • stand_id
  • ✅ assigned_by_reservation_allocator (true/false)

---

✈️ GET /stand/assignment/{callsign} (single assignment)

• Loads the latest assignment history for the returned assignment and includes:
  • id, airfield, identifier
  • ✅ assigned_by_reservation_allocator

---

🧩 Model enhancement: latest assignment history relationship

• Adds StandAssignment::assignmentHistory() relationship:
  • hasOne(StandAssignmentsHistory::class, 'callsign', 'callsign')->latestOfMany('assigned_at')
• This provides a clean way to fetch the most recent assignment provenance.

---

⚙️ Service optimisation

• StandAssignmentsService::assignmentForCallsign() now eager-loads:
  • assignmentHistory
• Helps avoid N+1 queries and ensures provenance is available wherever assignments are fetched.

---

🧪 Tests added/updated

• Existing assignment list + single assignment tests updated to expect:
  • assigned_by_reservation_allocator => false by default
• Adds two new tests to validate provenance detection:
  • ✅ testItReturnsReservationAllocatorSourceInStandAssignments
  • ✅ testItReturnsReservationAllocatorSourceForSingleAssignmentRoute
• Uses StandAssignmentsHistory::create() with type App\Allocator\Stand\UserRequestedArrivalStandAllocator to assert the flag becomes true.

---

✅ Net effect

Consumers (UI / plugin / API clients) can now distinguish normal user/auto assignments from those created via the reservation allocator, without changing existing endpoints or payload structure beyond the additive boolean field.

[sonarqubecloud]

Quality Gate passed

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
0.0% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarQube Cloud

[MrAdder]

Currently draft while I look into the Plugin side of things will also need changes in Lists_SMR and Lists as looking into adding this as a tag item