feat: optimistic polkadot rotation

[dandanlen]

Cherry picks.

Fixes #4178
Fixes #4171
Fixes #4185

[codecov]

Codecov Report

Merging #4182 (c36331d) into main (3fafc45) will increase coverage by 0%.
The diff coverage is 69%.

@@          Coverage Diff          @@
##            main   #4182   +/-   ##
=====================================
  Coverage     72%     72%           
=====================================
  Files        380     380           
  Lines      61841   61818   -23     
  Branches   61841   61818   -23     
=====================================
- Hits       44390   44384    -6     
+ Misses     15149   15119   -30     
- Partials    2302    2315   +13     

Files	Coverage Δ
state-chain/cf-integration-tests/src/network.rs	95% <100%> (-<1%)	⬇️
...ain/chains/src/dot/api/batch_fetch_and_transfer.rs	100% <100%> (ø)
...ate-chain/chains/src/dot/api/rotate_vault_proxy.rs	100% <100%> (ø)
state-chain/chains/src/lib.rs	29% <ø> (+5%)	⬆️
state-chain/runtime/src/lib.rs	35% <ø> (ø)
state-chain/chains/src/dot/benchmarking.rs	0% <0%> (ø)
...te-chain/pallets/cf-threshold-signature/src/lib.rs	78% <86%> (+<1%)	⬆️
engine/src/witness/dot.rs	28% <43%> (-1%)	⬇️
state-chain/chains/src/dot/api.rs	21% <20%> (+1%)	⬆️
state-chain/runtime/src/chainflip.rs	59% <62%> (+2%)	⬆️
... and 1 more

... and 6 files with indirect coverage changes

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