feat: add support for escaping json dot notation

[mhoff]

Description

• Briefly summarize your changes in a few bullet points (can and should correspond to CHANGELOG.md)
• Relates to #XXX (insert issue number here), if there is a corresponding GH issue

TODOs

Processors

• Processor calculator (syntax calc: ${duration} * 10e5)
• Processor decoder (dots in JSON, examples missing)
• Processor dissector(syntax message: "%{}of %{extracted.message_float}")
• Processor dropper (handling of fields in drop)
• Processor generic_adder (handling of fields in add)
• Processor grokker (syntax message: "%{TIMESTAMP_ISO8601:@timestamp} %{GREEDYDATA:logMessage}")
• Processor replacer (syntax message: "Message %{*} was created by user %{USER_ID}.")
• Processor requester (syntax hostname: ${message.hostname}, data, params, ...)
• Processor template_replacer (syntax %{provider_name}-%{event_id}: %{new_message})
• Processor timestamp_differ (syntax diff: ${t1:%Y-%m-%d %H:%M:%S} - ${t2:%Y-%m-%d %H:%M:%S})

Fields

• regex_fields
• source_fields
• add
• drop

Assignee

• The changes adhere to the contribution guidelines
• I have performed a self-review of my code
• My changes generate no new warnings (e.g. flake8/mypy/pytest/...) other than deprecations

Documentation

• README.md is up-to-date
• CHANGELOG.md is up-to-date
• Documentation (doc/source) is up-to-date
• Preview for docs looks fine
• Notebooks are up-to-date and functional
• Examples are up-to-date and functional (including compose & k8s)

Code Quality

• Patch test coverage > 95% and does not decrease
• New code uses correct & specific type hints

How did you verify that the changes work in practice?

• List of (preferably easy reproducible) tests including OS

Reviewer

• The code is readable/maintainable and follows the contribution guidelines
• Documentation is up-to-date
• Tests (unit & acceptance) are meaningful and not over-mocked

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[codecov-commenter]

Codecov Report

❌ Patch coverage is 95.85062% with 10 lines in your changes missing coverage. Please review.
✅ Project coverage is 96.12%. Comparing base (0e19175) to head (e085c6d).

Files with missing lines	Patch %	Lines
logprep/abc/input.py	94.11%	3 Missing ⚠️
logprep/framework/rule_tree/rule_tagger.py	57.14%	3 Missing ⚠️
logprep/ng/abc/input.py	94.23%	3 Missing ⚠️
logprep/util/grok_pattern_loader.py	75.00%	1 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #937      +/-   ##
==========================================
- Coverage   96.14%   96.12%   -0.02%     
==========================================
  Files         217      217              
  Lines       14219    14275      +56     
==========================================
+ Hits        13671    13722      +51     
- Misses        548      553       +5     

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