Support for module partitions, filter os-specific files

[kgorking]

No description provided.

[Copilot]

Pull request overview

This PR updates the GBS build pipeline to better support C++20 modules (including module partitions) and to filter OS-specific source files/directories based on the target OS.

Changes:

• Extend dependency scanning and build orchestration to account for module partitions and (some) WSL path cases.
• Add target-OS-aware source inclusion filtering (windows/linux/macos directories) and update callers to pass context.
• Update task graph execution to support task failure/abort signaling and add cycle detection diagnostics.

Reviewed changes

Copilot reviewed 15 out of 15 changed files in this pull request and generated 11 comments.

Show a summary per file

File	Description
launch.vs.json	Adds/adjusts VS launch profiles for running builds/tests.
gbs/src/task/task_graph.cpp	Adds cycle detection output; changes task execution to return bool and abort on failure.
gbs/inc/task/task_graph.h	Updates task API to bool-returning work items; adds cycle-path helper and abort state.
gbs/inc/task/task.h	Changes task work signature to bool; adds task_true.
gbs/src/os.cpp	Removes host-OS helpers now inlined in header.
gbs/inc/os.h	Inlines is_host_* consteval helpers.
gbs/src/get_source_groups.cpp	Adds OS-specific filtering and threads context through source enumeration.
gbs/inc/get_source_groups.h	Updates APIs to accept context.
gbs/src/dep_scan.cpp	Adds module partition parsing and WSL-path handling during dependency scan.
gbs/inc/dep_scan.h	Updates dependency-scan API to accept context.
gbs/src/cmd_build.cpp	Integrates new filtering + dependency scan; adds module dependency edges; changes tasks to return bool.
gbs/src/enumerate_compilers_clang.cpp	Makes temp file removal non-throwing; gates WSL enumeration to Windows.
gbs/src/enumerate_compilers.cpp	Adds os.h include (context for host/OS utilities).
gbs/src/context.cpp	Adjusts MSVC flags and enables clang std-module patching on Windows hosts.
.github/workflows/cmake-multi-platform.yml	Adds a Windows CI step that downloads and runs GBS to build + run unittests.

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[Copilot]

Pull request overview

Copilot reviewed 15 out of 15 changed files in this pull request and generated 4 comments.

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[Copilot]

@kgorking I've opened a new pull request, #73, to work on those changes. Once the pull request is ready, I'll request review from you.