third_party/rules_rust: Use musl toolchain and add loader_wrapper

Change-Id: Ia873e6bf43ed8f6f3c56943dba0e893b7efb7f44
Reviewed-on: https://review.monogon.dev/c/monogon/+/4310
Reviewed-by: Tim Windelschmidt <tim@monogon.tech>
Tested-by: Jenkins CI
diff --git a/MODULE.bazel.lock b/MODULE.bazel.lock
index d6edd57..ca91e77 100644
--- a/MODULE.bazel.lock
+++ b/MODULE.bazel.lock
@@ -1431,7 +1431,7 @@
     },
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       "general": {
-        "bzlTransitiveDigest": "8V+EjcJ6yZ+quaNMoFSCDIH+XDhCkjgCsiium78SdCY=",
+        "bzlTransitiveDigest": "PuAP2g4Ru+pBugsbmCEnQMOa3RC4MAiUwq3IARY4syY=",
         "usagesDigest": "Mw24CZ9hpdGUPbu/RcrRZS5Y/Az10OU968XzrSx9rUI=",
         "recordedFileInputs": {
           "@@//third_party/rust/Cargo.lock": "fa9d7f659ffbfb7f5554de4a7e653d3bd900f0a75b22ef4c0853b98c6ede5548",
@@ -2694,7 +2694,7 @@
     },
     "@@rules_rust+//crate_universe/private:internal_extensions.bzl%cu_nr": {
       "general": {
-        "bzlTransitiveDigest": "/lCPEYwxLjcUUzuJlryJJyzteuW5rxwGQ86cPPkUL9M=",
+        "bzlTransitiveDigest": "c2lNdp995IIrl9Z4g/h/k41gXEU73T2zNYqAIatm4/o=",
         "usagesDigest": "Pr9/2PR9/ujuo94SXikpx+fg31V4bDKobC10YJu+z5I=",
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