transform/subslice: Add subslice transform

[jlucovsky]

Continuation of #14643

The subslice transform creates a slice of the input buffer.

Specify the subslice desired -- nbytes and truncate are optional:
        subslice: offset <,nbytes> <,truncate>

offset: Specifies the starting offset for the new subslice. When
negative, expresses how far from the end of the input buffer to begin.
When nbytes is *not* specified, start must be > 0.

nbytes: Specifies the size of the subslice. When negative, specifies the
byte count preceding the offset to include. Nbytes must be > 0.

When nbytes is not specified, the size of the subslice will be the size
of the input buffer - offset.

truncate: Specify behavior when offset + nbytes exceeds buffer length.
When present, trims nbytes such that offset + nbytes equals buffer
length. When not present, an empty buffer is produced.

Examples:
subslice: 1; - The subslice will be a copy of the input
buffer but omit the input buffer's first byte
"This is Suricata" -> "his is Suricata"
subslice: 0, 13; - The slice is created from the first 13 bytes
of the input buffer
"This is Suricata" -> "This is Suric"
subslice: 10, -5; - This is the same as subslice[5, 5]
"This is Suricata" -> "is Su"
subslice: -3; - The subslice will be the last 3 bytes of the
input buffer.
"This is Suricata" -> "ata"

Link to ticket: https://redmine.openinfosecfoundation.org/issues/7672

Describe changes:

• Add subslice transform and unit tests
• Document subslice transform, with examples

Updates:

• Removed support for bracketed values, e.g., [3], [3, 8]`
• Changed function DetectTransformSubsliceData to be attributed with repr(C)
• Modified handling of negative nbyte values to mean "bytes from the end" .
• start=0 is an error unless nbytes is specified
• end=0 is always an error.
• Corrected clippy issues.
• Added configuration variable subslice.truncate to control behavior when offset + nbytes > length
• Updated s-v branch.
• Fixed s-v failing tests due to default config settings
• Rebase
• Fixed race condition in unittests wrt global variable
• Removed truncate global option and replaced with a per-usage truncate option.
• Rebase
• Doc update to remove lingering global truncate option.
• Removed commit that adjusted asn1 underline characters.
• Updated Rust unit tests to eliminate is_some usage.
• Removed inadvertent inclusion of Cargo.lock.in
• Applied truncate option to negative offsets/byte count exceeding buffer length.
• Reworked slice copy to handle input/output pointing to the same buffer.
• Expanded documention to include discussion on negative offset/nbytes exceeding buffer length.

Provide values to any of the below to override the defaults.

• To use a Suricata-Verify or Suricata-Update pull request,
  link to the pull request in the respective _BRANCH variable.
• Leave unused overrides blank or remove.

SV_REPO=
SV_BRANCH=OISF/suricata-verify#2749
SU_REPO=
SU_BRANCH=

[codecov]

Codecov Report

❌ Patch coverage is 97.39414% with 16 lines in your changes missing coverage. Please review.
✅ Project coverage is 82.20%. Comparing base (c1d6958) to head (6f58eb1).

Additional details and impacted files

@@            Coverage Diff             @@
##             main   #14751      +/-   ##
==========================================
+ Coverage   82.17%   82.20%   +0.03%     
==========================================
  Files        1008     1009       +1     
  Lines      263938   264552     +614     
==========================================
+ Hits       216878   217475     +597     
- Misses      47060    47077      +17     

Flag	Coverage Δ
fuzzcorpus	60.15% <10.12%> (-0.05%)	⬇️
livemode	18.75% <10.12%> (+0.02%)	⬆️
netns	18.53% <10.19%> (-0.04%)	⬇️
pcap	44.60% <10.12%> (-0.04%)	⬇️
suricata-verify	65.38% <85.35%> (+0.02%)	⬆️
unittests	59.43% <90.86%> (+0.07%)	⬆️

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[suricata-qa]

Information: QA ran without warnings.

Pipeline = 29413

[catenacyber]

Why is CI so red ? (rebase SV ?)