[paulbalandan]

Description
Follow-up to #10628. Adds the verbosity levels on top of the Output object.

• Every command gains --silent, --quiet / -q and --verbose / -v, -vv, -vvv. They have to ship with 4.8.0, so no third-party modern command claims the shortcuts first.
• SHELL_VERBOSITY sets the level when no flag is given. While the command runs, spark sets it to the level in use, so child processes inherit it, and restores it afterwards.
• Combined flags resolve to the quietest one (--silent > -q > -v), as in Symfony.
• The level is a new Verbosity enum held by Output.
  • print(), write() and newLine() take the lowest level that shows the text.
  • isQuiet(), isVerbose(), isVeryVerbose() and isDebug() guard larger blocks.
• Quiet drops normal writes but keeps errors, and silent drops errors too.
• Quiet makes a modern command non-interactive.
• Legacy commands follow the level, and still receive the flags as their own options.
• An uncaught exception shows its backtrace from -v on, after the app/Views/errors/cli/error_exception.php update (listed in the upgrade guide).
• lang:find uses the global --verbose in place of its own.

Checklist:

• Securely signed commits
• Component(s) with PHPDoc blocks, only if necessary or adds value (without duplication)
• Unit testing, with >80% coverage
• User guide updated
• Conforms to style guide

[Copilot]

🟡 Changes recommended

Numeric shortcuts fail during verbosity processing, and the documented options example conflicts with the new defaults.

2 open issues

• Handle numeric shortcuts without type errors or key renumbering · New
• Rename conflicting verbose option in modern commands example · New

What changed in this PR

Adds Spark verbosity controls for 4.8.0, building on the instance-based CLI output API.

Changes:

• Adds global verbosity flags, environment fallback, and output filtering.
• Integrates verbosity with command interaction, translation output, and exception backtraces.
• Updates tests, examples, and release documentation.

Validation used targeted source inspection; runtime tests remain for CI.

File	Description
user_guide_src/​source/​installation/​upgrade_480.rst	Documents exception-view update.
user_guide_src/​source/​cli/​spark_commands.rst	Explains flags and environment fallback.
user_guide_src/​source/​cli/​cli_modern_commands/​019.php	Demonstrates verbosity-aware output.
user_guide_src/​source/​cli/​cli_modern_commands.rst	Documents defaults and command integration.
user_guide_src/​source/​cli/​cli_library.rst	Documents output levels and APIs.
user_guide_src/​source/​changelogs/​v4.8.0.rst	Records verbosity support.
tests/​system/​Commands/​Translation/​LocalizationFinderTest.php	Tests verbose translation reporting.
tests/​system/​Commands/​HelpCommandTest.php	Updates expected help options.
tests/​system/​CLI/​OutputTest.php	Tests filtering and level predicates.
tests/​system/​CLI/​ConsoleTest.php	Tests flags and environment restoration.
tests/​system/​CLI/​AbstractGeneratorCommandTest.php	Updates expected generator defaults.
tests/​system/​CLI/​AbstractCommandTest.php	Tests defaults and quiet interaction.
tests/​_support/​Commands/​Modern/​VerbosityProbeCommand.php	Adds verbosity test fixture.
system/​Commands/​Translation/​LocalizationFinder.php	Uses global verbosity.
system/​CLI/​Verbosity.php	Defines output levels.
system/​CLI/​Output.php	Filters output by level.
system/​CLI/​Console.php	Resolves flags and manages environment state.
system/​CLI/​AbstractCommand.php	Registers flags and quiet interaction behavior.
app/​Views/​errors/​cli/​error_exception.php	Enables verbose backtraces.

_{Review effort: Balanced}