feat(commands)!: Add lock command

[aawsome]

see rustic-rs/rustic#1050

BREAKING CHANGES:

• DeleteOptions in SnapshotFile now has more enum options.
• Repository::save_snapshots now returns the list of Ids of the saved snapshots.

Missing points:

• Implement locking in the backends
• Add possibilities to lock key files
• Add possibility to lock complete repo
• Handle duplicate snapshots correctly - especially create at max. 1 new snapshot per "original" snapshot during lock
• Handle locks in forget command (retention policy: only count one/the original snapshot for retention)
• Handle locks correctly in the tag command (don't even try to remove locked snapshots)

[codecov]

Codecov Report

Attention: Patch coverage is 5.81395% with 162 lines in your changes missing coverage. Please review.

Project coverage is 44.0%. Comparing base (c504c29) to head (5a11725).

Files with missing lines	Patch %	Lines
crates/core/src/commands/lock.rs	0.0%	98 Missing ⚠️
crates/core/src/backend/lock.rs	0.0%	23 Missing ⚠️
crates/core/src/backend/decrypt.rs	0.0%	10 Missing ⚠️
crates/core/src/repository.rs	9.0%	10 Missing ⚠️
crates/core/src/backend.rs	0.0%	7 Missing ⚠️
crates/core/src/backend/dry_run.rs	0.0%	4 Missing ⚠️
crates/core/src/repository/warm_up.rs	0.0%	3 Missing ⚠️
crates/core/src/commands/forget.rs	60.0%	2 Missing ⚠️
crates/core/src/repofile/snapshotfile.rs	33.3%	2 Missing ⚠️
crates/core/src/commands/copy.rs	0.0%	1 Missing ⚠️
... and 2 more

Additional details and impacted files

Files with missing lines	Coverage Δ
crates/core/src/backend/cache.rs	73.5% <ø> (-1.9%)	⬇️
crates/core/src/backend/hotcold.rs	0.0% <ø> (ø)
crates/core/src/error.rs	71.4% <ø> (+14.2%)	⬆️
crates/core/src/commands/copy.rs	0.0% <0.0%> (ø)
crates/core/src/commands/prune.rs	72.0% <75.0%> (-0.1%)	⬇️
crates/core/src/repofile/indexfile.rs	86.6% <66.6%> (-5.0%)	⬇️
crates/core/src/commands/forget.rs	83.9% <60.0%> (-2.9%)	⬇️
crates/core/src/repofile/snapshotfile.rs	47.9% <33.3%> (-1.2%)	⬇️
crates/core/src/repository/warm_up.rs	17.0% <0.0%> (ø)
crates/core/src/backend/dry_run.rs	12.7% <0.0%> (-1.2%)	⬇️
... and 5 more

... and 18 files with indirect coverage changes