feat(foreign-cc): derive runtime library search directories

[jsun-splunk]

Add opt-in runtime library search directory derivation for foreign_cc
outputs. This lets foreign-built binaries and shared libraries resolve
shared libraries from deps, dynamic_deps, and this rule's own declared
shared-library outputs without relying on loader environment variables such
as LD_LIBRARY_PATH.

Public attrs:

• runtime_library_search_directories
• additional_dynamic_runtime_library_search_origins
• additional_executable_runtime_library_search_origins

Example:

configure_make(
    name = "python",
    out_binaries = ["python3.10"],
    out_shared_libs = ["libpython3.10.so"],
    runtime_library_search_directories = "enabled",
    additional_dynamic_runtime_library_search_origins = [
        "lib/python3.10/lib-dynload",
    ],
    deps = [":openssl"],
)

runtime_library_search_directories accepts auto, enabled, and
disabled. The global build setting defaults to disabled, so existing
targets keep the previous behavior unless a target opts in or the build
setting is enabled.

Default origins are derived from declared output File.short_path values.
Shared-library link actions use declared shared-library output directories.
Executable link actions use declared binary output directories. Additional
origins are install-tree-relative paths joined under this rule's INSTALLDIR.

The implementation derives dependency origins from LibraryToLink dynamic
libraries and adds Bazel _solib sibling search paths for solib symlink
layouts. Runtime search derivation is skipped for Windows C++ toolchains.

Wire the runtime search path flags as common implementation flags.
However, support is limited to cmake, configure_make, make and
meson. Ninja and boost support is currently disabled.

Add unit coverage for enablement, default origins, additional origins,
self-output search paths, _solib paths, deduplication, and global
build-setting resolution. Add integration coverage for runtime
dependency chains and self-contained output bundles.

Depends on #1401.