chore: use keyType instead of type for tss + bls keys

[joey-bai]

type was originally used to differentiate different types of backup keys
(i.e. using an external key provider or holding on to your own).

this was overloaded with the introduction of TSS and BLS.

this change refactors to use keyType to determine multisig type (tss,
bls, or independent/onchain).

Ticket: BG-43890

[joey-bai]

Note to reviewers: this comes from https://github.com/BitGo/bitgo-microservices/blob/develop/packages/api-docs/shared/KeyType.yaml

[codecov]

Codecov Report

Merging #2246 (499fdd5) into master (dbdbcfc) will increase coverage by 52.61%.
The diff coverage is n/a.

❗ Current head 499fdd5 differs from pull request most recent head 6cf05f2. Consider uploading reports for the commit 6cf05f2 to get more accurate results

@@             Coverage Diff             @@
##           master    #2246       +/-   ##
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+ Coverage        0   52.61%   +52.61%     
===========================================
  Files           0        6        +6     
  Lines           0      574      +574     
  Branches        0       94       +94     
===========================================
+ Hits            0      302      +302     
- Misses          0      262      +262     
- Partials        0       10       +10     

Flag	Coverage Δ
unit	52.61% <ø> (?)

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Impacted Files	Coverage Δ
modules/express/src/config.ts	94.73% <0.00%> (ø)
modules/express/src/errors.ts	82.35% <0.00%> (ø)
modules/express/src/args.ts	100.00% <0.00%> (ø)
modules/express/src/expressApp.ts	89.51% <0.00%> (ø)
modules/express/src/retryPromise.ts	11.76% <0.00%> (ø)
modules/express/src/clientRoutes.ts	32.48% <0.00%> (ø)