Implement Terminal.Gui.Cli core library API

[Copilot]

Terminal.Gui.Cli needs a reusable host layer for Terminal.Gui-backed commands: explicit command registration, typed results, stable JSON output, POSIX exit codes, help metadata, and AI-agent discoverability.

• Command API

  • Added command/result models, typed and untyped command interfaces, viewer command support, and command option descriptors.
  • Added CommandRegistry with case-insensitive alias resolution and duplicate rejection.

• Host and parsing

  • Added CliHost, CliHostOptions, CommandRunOptions, and ArgParser.
  • Centralized Terminal.Gui lifecycle ownership in CliHost.
  • Supports framework flags, consumer globals, per-command options, positional args, timeouts, --cat, --json, and output routing.

• Output and metadata

  • Added source-generated JsonEnvelope, ResultWriter, ExitCodes, TypeNames, and OpenCliWriter.
  • Added terminal escape sanitization and Markdown-to-ANSI rendering support.

• Built-ins and docs

  • Added metadata help provider, embedded markdown help provider, help, and agent-guide.
  • Documented the public API surface and required filename layout exceptions in specs/.

• Tests

  • Added focused unit coverage for registry behavior, parser behavior, JSON/result output, host metadata paths, and escape sanitization.

Example:

var host = new CliHost(options =>
{
    options.ApplicationName = "my-app";
    options.Version = "1.0.0";
    options.AgentGuide = "# Agent Guide";
    options.AgentGuideIsResource = false;
});

host.Registry.Register(new MyCommand());

int exitCode = await host.RunAsync(args);

[chatgpt-codex-connector]

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[tig]

@copilot see cr feedback. Write tests that fail for each before fixing.

[Copilot]

@copilot see cr feedback. Write tests that fail for each before fixing.

Addressed in 1a3ed7f. I added regression tests that failed before the fixes for timeout overflow and cancellation handling, then updated parsing/host behavior and reran local validation successfully.

[tig]

@copilot see review comments and address. Verify ci/cd uses the same code formatting/style check infrastructure)including running resharper cleanup. These issues should have caused the workflows in this pr to fail.

[Copilot]

@copilot see review comments and address. Verify ci/cd uses the same code formatting/style check infrastructure)including running resharper cleanup. These issues should have caused the workflows in th...

Addressed in 73eaae9. I ran ReSharper cleanup, committed the resulting style fixes, pinned JetBrains ReSharper GlobalTools, and updated CI/release workflows to run cleanupcode plus dotnet format and fail on diffs. Local restore/build/format/tests and CodeQL/code review validation passed; the new GitHub CI run is awaiting action before jobs are created.

Warning

Firewall rules blocked me from connecting to one or more addresses (expand for details)

I tried to connect to the following addresses, but was blocked by firewall rules:

• www.jetbrains.com
  • Triggering command: /usr/share/dotnet/dotnet /usr/share/dotnet/dotnet exec --runtimeconfig /home/REDACTED/.nuget/packages/jetbrains.resharper.globaltools/2026.1.2/tools/net8.0/any/cleanupcode.unix.runtimeconfig.json /home/REDACTED/.nuget/packages/jetbrains.resharper.globaltools/2026.1.2/tools/net8.0/any/cleanupcode.exe Terminal.Gui.Cli.slnx --verbosity=WARN (dns block)
  • Triggering command: /usr/share/dotnet/dotnet /usr/share/dotnet/dotnet exec --runtimeconfig /home/REDACTED/.nuget/packages/jetbrains.resharper.globaltools/2026.1.2/tools/net8.0/any/cleanupcode.unix.runtimeconfig.json /home/REDACTED/.nuget/packages/jetbrains.resharper.globaltools/2026.1.2/tools/net8.0/any/cleanupcode.exe Terminal.Gui.Cli.slnx --no-build --verbosity=WARN (dns block)
  • Triggering command: /usr/share/dotnet/dotnet /usr/share/dotnet/dotnet exec --runtimeconfig /home/REDACTED/.nuget/packages/jetbrains.resharper.globaltools/2026.1.2/tools/net8.0/any/cleanupcode.unix.runtimeconfig.json /home/REDACTED/.nuget/packages/jetbrains.resharper.globaltools/2026.1.2/tools/net8.0/any/cleanupcode.exe Terminal.Gui.Cli.slnx --no-build --verbosity=WARN dRestoreSessionId=3149c03f-4cbd-416d-a1e2-6ed806ac89a9;MSBuildIsRestoring=True;ExcludeRestorePackageImports=True;OriginalMSBuildStartupDirectory=/usr/share/dotnet/sdk/10.0.300 (dns block)

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