eliminate stderr usage in std.Build make() functions

* Eliminate all uses of `std.debug.print` in make() functions, instead
  properly using the step failure reporting mechanism.
* Introduce the concept of skipped build steps. These do not cause the
  build to fail, and they do allow their dependants to run.
* RunStep gains a new flag, `skip_foreign_checks` which causes the
  RunStep to be skipped if stdio mode is `check` and the binary cannot
  be executed due to it being a foreign executable.
  - RunStep is improved to automatically use known interpreters to
    execute binaries if possible (integrating with flags such as
    -fqemu and -fwasmtime). It only does this after attempting a native
    execution and receiving a "exec file format" error.
  - Update RunStep to use an ArrayList for the checks rather than this
    ad-hoc reallocation/copying mechanism.
  - `expectStdOutEqual` now also implicitly adds an exit_code==0 check
    if there is not already an expected termination. This matches
    previously expected behavior from older API and can be overridden by
    directly setting the checks array.
* Add `dest_sub_path` to `InstallArtifactStep` which allows choosing an
  arbitrary subdirectory relative to the prefix, as well as overriding
  the basename.
  - Delete the custom InstallWithRename step that I found deep in the
    test/ directory.
* WriteFileStep will now update its step display name after the first
  file is added.
* Add missing stdout checks to various standalone test case build
  scripts.

lib/std/Build/InstallArtifactStep.zig

@@ -12,6 +12,9 @@ artifact: *CompileStep,
 dest_dir: InstallDir,
 pdb_dir: ?InstallDir,
 h_dir: ?InstallDir,
+/// If non-null, adds additional path components relative to dest_dir, and
+/// overrides the basename of the CompileStep.
+dest_sub_path: ?[]const u8,
 
 pub fn create(owner: *std.Build, artifact: *CompileStep) *InstallArtifactStep {
     if (artifact.install_step) |s| return s;
@@ -40,6 +43,7 @@ pub fn create(owner: *std.Build, artifact: *CompileStep) *InstallArtifactStep {
             }
         } else null,
         .h_dir = if (artifact.kind == .lib and artifact.emit_h) .header else null,
+        .dest_sub_path = null,
     };
     self.step.dependOn(&artifact.step);
     artifact.install_step = self;
@@ -71,7 +75,9 @@ fn make(step: *Step, prog_node: *std.Progress.Node) !void {
     const self = @fieldParentPtr(InstallArtifactStep, "step", step);
     const dest_builder = self.dest_builder;
 
-    const full_dest_path = dest_builder.getInstallPath(self.dest_dir, self.artifact.out_filename);
+    const dest_sub_path = if (self.dest_sub_path) |sub_path| sub_path else self.artifact.out_filename;
+    const full_dest_path = dest_builder.getInstallPath(self.dest_dir, dest_sub_path);
+
     try src_builder.updateFile(
         self.artifact.getOutputSource().getPath(src_builder),
         full_dest_path,