op-challenger: Lazy create clients

[ajsutton]

Description

Only create the l2 and rollup clients when a game type actually needs them.

Make sync validator configurable per game type since we'll need a different implementation for super root games.

[codecov]

Codecov Report

Attention: Patch coverage is 0% with 84 lines in your changes missing coverage. Please review.

Project coverage is 42.85%. Comparing base (96f78bb) to head (468524f).

Files with missing lines	Patch %	Lines
op-challenger/game/fault/clients.go	0.00%	37 Missing ⚠️
op-challenger/game/fault/register.go	0.00%	34 Missing ⚠️
op-challenger/game/fault/register_task.go	0.00%	13 Missing ⚠️

Additional details and impacted files

@@             Coverage Diff             @@
##           develop   #13810      +/-   ##
===========================================
- Coverage    47.17%   42.85%   -4.32%     
===========================================
  Files          965      800     -165     
  Lines        80468    71088    -9380     
  Branches       774        0     -774     
===========================================
- Hits         37963    30467    -7496     
+ Misses       39578    37958    -1620     
+ Partials      2927     2663     -264     

Flag	Coverage Δ
cannon-go-tests-32	?
cannon-go-tests-64	?
contracts-bedrock-tests	?

Flags with carried forward coverage won't be shown. Click here to find out more.

Files with missing lines	Coverage Δ
op-challenger/game/fault/register_task.go	6.25% <0.00%> (-0.17%)	⬇️
op-challenger/game/fault/register.go	0.00% <0.00%> (ø)
op-challenger/game/fault/clients.go	0.00% <0.00%> (ø)

... and 171 files with indirect coverage changes