UML-3136: Update viewer journey templates to support combined LPAs

[acsauk]

Purpose

So, this was a bit of a slog, but from testing the viewer journey for the current LPA format, combined Sirius, and combined LPA-store LPAs, it looks like it's working.

I went with new templates to support the combined LPA rather than adding logic to existing templates as this felt a bit cleaner and should hopefully have less cleanup in the future.

I made an attempt to start the API work that would be required to support this once the mock API response is removed but the PR was already getting huge so I moved it to its own branch. Feel free to disregard if the API work isn't picked up for a while as it will quickly be outdated.

I ran out of time before I could add behat tests but it may be worth waiting to implement them when the data model has solidified and the API side has been implemented.

I made a few additions to the front end unit tests such as using some test helpers rather than relying on JSON files to get an LPA instrumented and ready to test.

Hopefully, this all makes sense and I haven't made any rash assumptions on the format of things but shout up if you want to talk through any of the PR and we can jump on a call.

Fixes UML-3136

[codecov]

Codecov Report

Attention: Patch coverage is 96.10390% with 6 lines in your changes missing coverage. Please review.

Project coverage is 91.78%. Comparing base (f00760a) to head (eaa64f1).
Report is 168 commits behind head on main.

Files with missing lines	Patch %	Lines
...ce-front/app/src/Common/src/Entity/CombinedLpa.php	90.90%	2 Missing ⚠️
service-front/app/src/Common/src/Entity/Person.php	92.85%	2 Missing ⚠️
...ervice-front/app/src/Common/src/Entity/Address.php	94.73%	1 Missing ⚠️
...src/Entity/Casters/ExtractPostcodeFromLpaStore.php	75.00%	1 Missing ⚠️

Additional details and impacted files

@@             Coverage Diff              @@
##               main    #2903      +/-   ##
============================================
+ Coverage     91.25%   91.78%   +0.53%     
- Complexity     1504     1765     +261     
============================================
  Files           309      383      +74     
  Lines          6393     8196    +1803     
============================================
+ Hits           5834     7523    +1689     
- Misses          542      656     +114     
  Partials         17       17              

Flag	Coverage Δ
use-an-lpa-admin	78.85% <ø> (-0.41%)	⬇️
use-an-lpa-api	97.22% <ø> (-0.15%)	⬇️
use-an-lpa-front	90.53% <96.10%> (+0.99%)	⬆️

Files with missing lines	Coverage Δ
...rc/Common/src/Entity/Casters/CastToCaseSubtype.php	100.00% <100.00%> (ø)
...Entity/Casters/CastToHowAttorneysMakeDecisions.php	100.00% <100.00%> (ø)
...c/Entity/Casters/CastToLifeSustainingTreatment.php	100.00% <100.00%> (ø)
...n/src/Entity/Casters/CastToWhenTheLpaCanBeUsed.php	100.00% <100.00%> (ø)
...nt/app/src/Common/src/Entity/LpaStore/LpaStore.php	100.00% <100.00%> (ø)
...rc/Common/src/Entity/LpaStore/LpaStoreAttorney.php	100.00% <100.00%> (ø)
...p/src/Common/src/Entity/LpaStore/LpaStoreDonor.php	100.00% <100.00%> (ø)
.../src/Entity/LpaStore/LpaStoreTrustCorporations.php	90.90% <100.00%> (ø)
...ont/app/src/Common/src/Entity/Sirius/SiriusLpa.php	100.00% <100.00%> (ø)
...src/Common/src/Entity/Sirius/SiriusLpaAttorney.php	100.00% <ø> (ø)
... and 15 more

... and 193 files with indirect coverage changes