feat: unwrap cause from UnexpectedException

[pablojhl]

This unwraps the failure's cause from an UnexpectedException. The main purpose of this is to simplify the error analysis

[tim-hm]

I'm swamped with other priority tasks at the moment so apologies I haven't been able to actually run this! But given a hasty review it looks good to me.

[github-actions]

Coverage Report for ./client-vms

Status	Category	Percentage	Covered / Total
🔵	Lines	90.51%	2299 / 2540
🔵	Statements	90.51%	2299 / 2540
🔵	Functions	84.83%	235 / 277
🔵	Branches	93.73%	419 / 447

File Coverage

File	Stmts	Branches	Functions	Lines	Uncovered Lines
Changed Files
client-vms/src/util.ts	94.28%	90.9%	100%	94.28%	29-30
client-vms/src/payment/client.ts	97.4%	95.23%	78.94%	97.4%	153-154, 166-167, 196
client-vms/src/vm/builder.ts	89.61%	73.07%	100%	89.61%	137-141, 180-182, 184-189, 198-199
client-vms/src/vm/operation/delete-values.ts	100%	100%	92.3%	100%
client-vms/src/vm/operation/invoke-compute.ts	96.02%	96.96%	100%	96.02%	109-114
client-vms/src/vm/operation/overwrite-permissions.ts	99.07%	100%	92.85%	99.07%	61
client-vms/src/vm/operation/query-pool-status.ts	100%	100%	91.66%	100%
client-vms/src/vm/operation/retrieve-compute-result.ts	95%	92.59%	92.3%	95%	62, 96-99
client-vms/src/vm/operation/retrieve-permissions.ts	98.97%	100%	92.85%	98.97%	60
client-vms/src/vm/operation/retrieve-values.ts	100%	100%	92.85%	100%
client-vms/src/vm/operation/store-program.ts	100%	100%	92.85%	100%
client-vms/src/vm/operation/store-values.ts	95.74%	96.55%	93.75%	95.74%	93-98
client-vms/src/vm/operation/update-permissions.ts	76.02%	100%	50%	76.02%	170-172, 175-177, 180-182, 185-187, 190-192, 195-197, 200-202, 205-207, 210-212, 220-222, 225-227, 230-237

Generated in workflow #79 for commit b7a15fb by the Vitest Coverage Report Action