docs(format): include API docs for each language/tool (#251)

* docs(format): include API docs for each language/tool

This makes it more clear that there's a 'yaml' attribute and you can set it to 'False', for example.
In a follow-up PR we can consider whether 'False' should be the default instead.

* refactor: don't provide format tool defaults

example/WORKSPACE.bazel

@@ -286,9 +286,7 @@ fetch_ktlint()
 
 ########################
 # Optional: multitool provides defaults for some tools such as yamlfmt
-# If you do not set up multitool, you will be forced to either set an explicit tool
-# for languages that have a default, or set explicit False value, e.g.
-#   format_multirun(jsonnet = False)
+# If you do not set up multitool, you must provide these tools yourself
 load("@rules_multitool//multitool:multitool.bzl", "multitool")
 
 multitool(

example/tools/format/BUILD.bazel

@@ -54,21 +54,26 @@ format_multirun(
     name = "format",
     cc = "@llvm_toolchain_llvm//:bin/clang-format",
     css = ":prettier",
+    go = "@aspect_rules_lint//format:gofumpt",
     html = ":prettier",
     # You can use standard gofmt instead of stricter gofumpt:
     # go = "@go_sdk//:bin/gofmt",
     java = ":java-format",
     javascript = ":prettier",
+    jsonnet = "@aspect_rules_lint//format:jsonnetfmt",
     kotlin = ":ktfmt",
     markdown = ":prettier",
     protocol_buffer = "//tools/lint:buf",
     python = "//tools/lint:ruff",
     rust = "@rules_rust//tools/rustfmt:upstream_rustfmt",
     scala = ":scalafmt",
+    shell = "@aspect_rules_lint//format:shfmt",
     sql = ":prettier",
     starlark = "@buildifier_prebuilt//:buildifier",
     swift = ":swiftformat",
+    terraform = "@aspect_rules_lint//format:terraform",
     visibility = ["//:__subpackages__"],
+    yaml = "@aspect_rules_lint//format:yamlfmt",
 )
 
 format_test(

format/BUILD.bazel

@@ -1,11 +1,22 @@
 load("@bazel_skylib//:bzl_library.bzl", "bzl_library")
+load("//format/private:formatter_binary.bzl", "BUILTIN_TOOL_LABELS")
+
+package(default_visibility = ["//visibility:public"])
 
 exports_files(glob(["*.bzl"]))
 
+# Alias the multitools for strict repo visibility under bzlmod
+[
+    alias(
+        name = v.split("/")[-1],
+        actual = v,
+    )
+    for v in BUILTIN_TOOL_LABELS.values()
+]
+
 bzl_library(
     name = "defs",
     srcs = ["defs.bzl"],
-    visibility = ["//visibility:public"],
     deps = [
         "//format/private:formatter_binary",
         "@aspect_bazel_lib//lib:lists",
@@ -17,7 +28,6 @@ bzl_library(
 bzl_library(
     name = "repositories",
     srcs = ["repositories.bzl"],
-    visibility = ["//visibility:public"],
     deps = [
         "@bazel_tools//tools/build_defs/repo:http.bzl",
         "@bazel_tools//tools/build_defs/repo:utils.bzl",