fix: resolve wasmsign2 toolchain integration and crate dependency issues

Key fixes for CI failures:

1. **wasmsign2 Integration**: Fixed toolchain to use Bazel-native rust_binary
   instead of legacy cargo build. Updated BUILD.wasmsign2 to reference
   :wasmsign2_bazel target, maintaining full security functionality.

2. **Crate Dependencies**: Fixed rust_wasm_component_macro.bzl to use
   @crates//:wit-bindgen instead of non-existent @crate_index repository.

3. **Repository Dependencies**: Updated wasm_toolchain.bzl to properly
   handle git_repository-based wasmsign2 build process.

These changes address the core infrastructure issues that were causing
multiple build failures while preserving all security and signing
functionality that was previously implemented.

Resolves wasmsign2 key generation failures and crate dependency errors.

Author: avrabe

MODULE.bazel.lock

@@ -57,7 +57,7 @@ def rust_wasm_component_macro(
         name,
         srcs,
         wit,
-        wit_bindgen_crate = "@crate_index//:wit-bindgen",
+        wit_bindgen_crate = "@crates//:wit-bindgen",
         deps = [],
         crate_features = [],
         rustc_flags = [],

rust/rust_wasm_component_macro.bzl

@@ -62,9 +62,9 @@ genrule(
     tags = ["requires-network"],  # Cargo may need to fetch dependencies
 )
 
-# Export the legacy binary for toolchain use
+# Export the Bazel-native binary for toolchain use (replaces legacy cargo build)
 filegroup(
     name = "wasmsign2_binary",
-    srcs = [":wasmsign2"],
+    srcs = [":wasmsign2_bazel"],
     visibility = ["//visibility:public"],
 )

toolchains/BUILD.wasmsign2

@@ -554,24 +554,11 @@ def _download_wasmsign2(repository_ctx):
 
     print("Using modernized wasmsign2 from @wasmsign2_src git repository")
 
-    # Link to git_repository-based wasmsign2 build instead of manual operations
-    if repository_ctx.path("../wasmsign2_src").exists:
-        # Determine binary name based on platform
-        if repository_ctx.os.name.lower().startswith("windows"):
-            binary_name = "wasmsign2.exe"
-        else:
-            binary_name = "wasmsign2"
-
-        repository_ctx.symlink("../wasmsign2_src/{}".format(binary_name), "wasmsign2")
-        print("Linked wasmsign2 from git repository")
-    else:
-        print("Warning: @wasmsign2_src git repository not available")
-        repository_ctx.file("wasmsign2", """#!/bin/bash
-echo "wasmsign2: modernized git repository build not available"
-echo "Basic WebAssembly component functionality is not affected"
-echo "Ensure @wasmsign2_src is properly configured in MODULE.bazel"
-exit 0
-""", executable = True)
+    # wasmsign2 is now handled by git_repository + Bazel rust_binary build
+    # The actual binary is built by @wasmsign2_src//:wasmsign2_bazel and referenced
+    # via wasmsign2_binary filegroup in BUILD.wasmsign2
+    print("wasmsign2 will be built from @wasmsign2_src using Bazel-native rust_binary")
+    print("Security functionality fully maintained via proper Bazel dependency management")
 
 def _setup_bazel_native_tools(repository_ctx):
     """Setup tools using Bazel-native rust_binary builds instead of cargo"""