Stop orchestrator for ff_system when moving to network V2

[awrichar]

Part of FIR-12
In a chain with #883
In a chain with #890

Background: The legacy ff_system namespace is created (ie an orchestrator and managers are initialized) whenever the default namespace is a V1 multiparty network. The ff_system namespace is initialized with an exact duplicate of the default namespace config (same plugins, same contract addresses, etc).

With this PR, if the default namespace (and therefore ff_system) migrates to V2 rules, the ff_system orchestrator will be stopped and removed, along with all its children.

This should allow legacy networks to cleanly migrate to V2 rules and retire ff_system. Notable caveat: once the default namespace is on V2, no other V1 namespaces will be supported.

[codecov-commenter]

Codecov Report

Merging #884 (5cb91d0) into main (995d53b) will decrease coverage by 0.00%.
The diff coverage is 100.00%.

❗ Current head 5cb91d0 differs from pull request most recent head 3a39360. Consider uploading reports for the commit 3a39360 to get more accurate results

@@            Coverage Diff             @@
##             main     #884      +/-   ##
==========================================
- Coverage   99.96%   99.96%   -0.01%     
==========================================
  Files         298      298              
  Lines       19563    19424     -139     
==========================================
- Hits        19557    19418     -139     
  Misses          5        5              
  Partials        1        1              

Impacted Files	Coverage Δ
cmd/firefly.go	100.00% <100.00%> (ø)
internal/multiparty/manager.go	100.00% <100.00%> (ø)
internal/namespace/manager.go	100.00% <100.00%> (ø)
internal/orchestrator/orchestrator.go	100.00% <100.00%> (ø)
internal/tokens/fftokens/fftokens.go	99.56% <0.00%> (-0.01%)	⬇️
pkg/core/data.go	100.00% <0.00%> (ø)
pkg/core/group.go	100.00% <0.00%> (ø)
pkg/core/message.go	100.00% <0.00%> (ø)
pkg/core/datatype.go	100.00% <0.00%> (ø)
pkg/core/identity.go	100.00% <0.00%> (ø)
... and 64 more

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[awrichar]

I think this should go in after #891 in order to leverage the caching logic there. Maybe after #890 as well. Moving to draft until some of these others clear out.

[awrichar]

Alright - this is rebased and ready now.