ci: Integrate ccache into MSVC build #24540

ccache 4.6:

Added support for caching calls to Microsoft Visual C++ (MSVC)

Integrated into our native Windows CI task.

On master (c109e7d51c9c5614aafce184c63b52ad2e859eb2):

This PR:

Summary:
  Hits:             222 /  222 (100.0 %)
    Direct:         222 /  222 (100.0 %)
    Preprocessed:     0 /    0
  Misses:             0
    Direct:           0
    Preprocessed:     0
  Errors:             7
  Uncacheable:        9
Primary storage:
  Hits:             444 /  444 (100.0 %)
  Misses:             0
  Cache size (GB): 0.04 / 5.00 (0.86 %)

Use the -v/--verbose option for more details.

cc @sipsorcery @MarcoFalke

@hebasto makes sense if you trust the caching tool to correctly detect source file changes etc.

Personally I don't trust compilers, let alone caching tools, enough to get it right with large source code bases, such as Bitcoin Core, and alawys do a clean; build.

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Conflicts

Reviewers, this pull request conflicts with the following ones:

• #24668 (build, qt: bump Qt5 version to 5.15.3 by prusnak)

If you consider this pull request important, please also help to review the conflicting pull requests. Ideally, start with the one that should be merged first.

Should be easy to revert if something goes wrong