Move previous_release dependency out of WORKSPACE.bzlmod and into MODULE.bazel

While I was at it, I upgraded the previous release to 29.0.

`PROTOBUF_PREVIOUS_RELEASE` is not currently getting updated, and I deleted it
because I don't see an obvious way of referring to it from `MODULE.bazel`.
Hopefully soon we can drop it from `WORKSPACE` and then the only place to
update will be `MODULE.bazel`.

PiperOrigin-RevId: 743211189

MODULE.bazel

@@ -237,3 +237,15 @@ archive_override(
         "@com_google_protobuf//:patches/protobuf_v25/0006-Add-repo_name.patch",
     ],
 )
+
+bazel_dep(name = "com_google_protobuf_previous_release", version = "29.0", dev_dependency = True)
+archive_override(
+    module_name = "com_google_protobuf_previous_release",
+    integrity = "sha256-EKDVjzmhqQnpXgDougtbHcZNApl/dBFRlTorNln254w=",
+    strip_prefix = "protobuf-29.0",
+    urls = ["https://github.com/protocolbuffers/protobuf/releases/download/v29.0/protobuf-29.0.tar.gz"],
+    patch_strip = 1,
+    patches = [
+        "@com_google_protobuf//:patches/protobuf_v29/0001-Update-module-name.patch",
+    ],
+)

WORKSPACE

@@ -317,12 +317,11 @@ http_archive(
 )
 
 # For checking breaking changes to well-known types from the previous release version.
-load("//:protobuf_version.bzl", "PROTOBUF_PREVIOUS_RELEASE")
-
 http_archive(
     name = "com_google_protobuf_previous_release",
-    strip_prefix = "protobuf-" + PROTOBUF_PREVIOUS_RELEASE,
-    url = "https://github.com/protocolbuffers/protobuf/releases/download/v{0}/protobuf-{0}.tar.gz".format(PROTOBUF_PREVIOUS_RELEASE),
+    integrity = "sha256-EKDVjzmhqQnpXgDougtbHcZNApl/dBFRlTorNln254w=",
+    strip_prefix = "protobuf-29.0",
+    urls = ["https://github.com/protocolbuffers/protobuf/releases/download/v29.0/protobuf-29.0.tar.gz"],
 )
 
 http_archive(

WORKSPACE.bzlmod

@@ -1,16 +1,3 @@
 # This is a WORKSPACE file used by bzlmod in combination with MODULE.bazel.
 # It's used for a gradual migration and it should be empty.
 # Don't remove this file. If the file doesn't exist, bzlmod falls back to WORKSPACE file.
-
-load("@bazel_tools//tools/build_defs/repo:http.bzl", "http_archive")
-
-# Following are just needed to run conformance tests, not really needed to support them via MODULE.bazel
-
-# Needed for checking breaking changes from the previous release version.
-load("//:protobuf_version.bzl", "PROTOBUF_PREVIOUS_RELEASE")
-
-http_archive(
-    name = "com_google_protobuf_previous_release",
-    strip_prefix = "protobuf-" + PROTOBUF_PREVIOUS_RELEASE,
-    url = "https://github.com/protocolbuffers/protobuf/releases/download/v{0}/protobuf-{0}.tar.gz".format(PROTOBUF_PREVIOUS_RELEASE),
-)

patches/protobuf_v29/0001-Update-module-name.patch

@@ -0,0 +1,13 @@
+diff --git a/MODULE.bazel b/MODULE.bazel
+index 400186b53..1194db9ca 100644
+--- a/MODULE.bazel
++++ b/MODULE.bazel
+@@ -2,7 +2,7 @@
+ # https://github.com/protocolbuffers/protobuf/issues/14313
+ 
+ module(
+-    name = "protobuf",
++    name = "com_google_protobuf_previous_release",
+     version = "29.0",  # Automatically updated on release
+     compatibility_level = 1,
+     repo_name = "com_google_protobuf",

protobuf_version.bzl

@@ -5,4 +5,3 @@ PROTOBUF_PYTHON_VERSION = "6.31.0"
 PROTOBUF_PHP_VERSION = "4.31.0"
 PROTOBUF_RUBY_VERSION = "4.31.0"
 PROTOBUF_RUST_VERSION = "4.31.0"
-PROTOBUF_PREVIOUS_RELEASE = "28.0-rc1"