Renaming the flogger package and the backing classes

[alexander-yevsyukov]

This PR renames the flogger package and directories to jvm. Also the classes starting from Flogger or Fluent were renamed.

The Middleman name

The name was selected as a temporary measure.
It hints on the plan that these classes or interfaces will be merged in with those having similar responsibilities in the jvmMain source set of the logging module.

This is planned for the one of the following PRs this or next week.

Next steps

• Convert the middleware to Kotlin.
• Merge the middleware package into jvmMain source set of the logging module.

[codecov]

Codecov Report

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Additional details and impacted files

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  Coverage          ?   59.57%           
  Complexity        ?      795           
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  Files             ?      116           
  Lines             ?     3871           
  Branches          ?      506           
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  Hits              ?     2306           
  Misses            ?     1364           
  Partials          ?      201           

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[armiol]

@alexander-yevsyukov see my comments so far. 86 / 297 reviewed.

[Copilot]

Pull Request Overview

This PR renames the "flogger" package and related classes to "jvm" while updating copyright years and comments to reflect the new naming.

• Package renaming in context, backend, parser, and API classes
• Renaming of logger API interfaces (e.g. FloggerApi to MiddlemanApi) and updating associated references
• Adjusted copyright notices and documentation comments for historical context

Reviewed Changes

Copilot reviewed 131 out of 300 changed files in this pull request and generated no comments.

Show a summary per file

File	Description
jvm/middleware/src/main/java/io/spine/logging/jvm/context/ContextDataProvider.java	Updated package name from "flogger.context" to "jvm.context" and corresponding imports and comments.
jvm/middleware/src/main/java/io/spine/logging/jvm/backend/package-info.java	Updated package name in package-info and updated copyright notice.
jvm/middleware/src/main/java/io/spine/logging/jvm/backend/TemplateContext.java	Changed package and import references accordingly.
jvm/middleware/src/main/java/io/spine/logging/jvm/backend/SimpleMessageFormatter.java	Added new file with proper copyright and package updates.
jvm/middleware/src/main/java/io/spine/logging/jvm/backend/Platform.java	Updated package name; adjusted documentation comments.
jvm/middleware/src/main/java/io/spine/logging/jvm/backend/MetadataProcessor.java	Added new file with proper refactoring from "flogger" to "jvm".
jvm/middleware/src/main/java/io/spine/logging/jvm/backend/MetadataKeyValueHandlers.java	Package and copyright updates.
jvm/middleware/src/main/java/io/spine/logging/jvm/backend/MetadataHandler.java	Updated package declaration and documentation references.
jvm/middleware/src/main/java/io/spine/logging/jvm/backend/Metadata.java	Renamed package references inside to "jvm.backend" and updated links.
jvm/middleware/src/main/java/io/spine/logging/jvm/backend/MessageUtils.java	Updated package references and links for historical context.
jvm/middleware/src/main/java/io/spine/logging/jvm/backend/LoggingException.java	Package and copyright changes.
jvm/middleware/src/main/java/io/spine/logging/jvm/backend/LoggerBackend.java	Updated package and documentation references; reformatted code comments.
jvm/middleware/src/main/java/io/spine/logging/jvm/backend/LogMessageFormatter.java	Updated package and documentation links.
jvm/middleware/src/main/java/io/spine/logging/jvm/backend/LogData.java	Added new file with package and copyright changes.
jvm/middleware/src/main/java/io/spine/logging/jvm/backend/KeyValueFormatter.java	New file with package and refactored formatting comments.
jvm/middleware/src/main/java/io/spine/logging/jvm/backend/FormatType.java	Renamed and updated package and documentation references.
jvm/middleware/src/main/java/io/spine/logging/jvm/backend/FormatOptions.java	New file with package and copyright updates.
jvm/middleware/src/main/java/io/spine/logging/jvm/backend/FormatChar.java	New file with package and refactored API for format characters.
jvm/middleware/src/main/java/io/spine/logging/jvm/backend/Clock.java	Package renaming in clock API.
jvm/middleware/src/main/java/io/spine/logging/jvm/backend/BaseMessageFormatter.java	New file with package renaming and updated formatting logic.
jvm/middleware/src/main/java/io/spine/logging/jvm/backend/BackendFactory.java	Package renaming in backend factory API.
jvm/middleware/src/main/java/io/spine/logging/jvm/StackSize.java	Package renaming and updated documentation.
jvm/middleware/src/main/java/io/spine/logging/jvm/StackBasedLogSite.java	Renamed parent class from FloggerLogSite to JvmLogSite and updated package references.
jvm/middleware/src/main/java/io/spine/logging/jvm/SpecializedLogSiteKey.java	Package and documentation updates.
jvm/middleware/src/main/java/io/spine/logging/jvm/SamplingRateLimiter.java	New file with package renaming and rate limiting logic.
jvm/middleware/src/main/java/io/spine/logging/jvm/RateLimitStatus.java	New file with package and documentation updates regarding rate limit operations.
jvm/middleware/src/main/java/io/spine/logging/jvm/MiddlemanApi.java	Renamed logging API interface from FloggerApi to MiddlemanApi and updated method signatures accordingly.
jvm/middleware/src/main/java/io/spine/logging/jvm/Middleman.java	Renamed logger implementation from FluentLogger2 to Middleman and updated API references.
jvm/middleware/src/main/java/io/spine/logging/jvm/MetadataKey.java	Renamed FloggerMetadataKey to MetadataKey and updated utility imports and documentation.
jvm/middleware/src/main/java/io/spine/logging/jvm/LoggingScopeProvider.java	Package renaming in scope provider with updated documentation references.

Files not reviewed (2)

• .idea/inspectionProfiles/Project_Default.xml: Language not supported
• .idea/kotlinc.xml: Language not supported