azure-cli-extensions: update docs on adding extension

Closes https://github.com/NixOS/nixpkgs/issues/342214

Signed-off-by: Paul Meyer <[e-mail]>

pkgs/by-name/az/azure-cli/README.md

···
 and the name of the extension you want to package as `extension`:
 
 ```sh
-./query-extension-index.sh --cli-version=2.61.0 --extension=azure-devops --download
+nix run .#azure-cli.extension-tool -- \
+  --cli-version=2.61.0 \
+  --extension=azure-devops \
+  --init
 ```
 
 The output should look something like this:
···
 ```json
 {
   "pname": "azure-devops",
-  "description": "Tools for managing Azure DevOps.",
-  "version": "1.0.1",
-  "url": "https://github.com/Azure/azure-devops-cli-extension/releases/download/20240514.1/azure_devops-1.0.1-py2.py3-none-any.whl",
-  "sha256": "f300d0288f017148514ebe6f5912aef10c7a6f29bdc0c916b922edf1d75bc7db",
+  "version": "1.0.2",
+  "url": "https://github.com/Azure/azure-devops-cli-extension/releases/download/20250624.2/azure_devops-1.0.2-py2.py3-none-any.whl",
+  "hash": "sha256-4rDeAqOnRRKMP26MJxG4u9vBuos6/SQIoVgfNbBpulk=",
+  "description": "Tools for managing Azure DevOps",
   "license": "MIT",
-  "requires": [
-    "distro (==1.3.0)",
-    "distro==1.3.0"
+  "requirements": [
+    "distro (>=1.6.0)"
   ]
 }
 ```
···
 ```nix
   azure-devops = mkAzExtension {
     pname = "azure-devops";
-    version = "1.0.0";
-    url = "https://github.com/Azure/azure-devops-cli-extension/releases/download/20240206.1/azure_devops-${version}-py2.py3-none-any.whl";
-    sha256 = "658a2854d8c80f874f9382d421fa45abf6a38d00334737dda006f8dec64cf70a";
+    version = "1.0.2";
+    url = "https://github.com/Azure/azure-devops-cli-extension/releases/download/20250624.2/azure_devops-${version}-py2.py3-none-any.whl";
+    hash = "sha256-4rDeAqOnRRKMP26MJxG4u9vBuos6/SQIoVgfNbBpulk=";
     description = "Tools for managing Azure DevOps";
     propagatedBuildInputs = with python3Packages; [
       distro
···
 
 * The attribute name should be the same as `pname`.
 * Replace the version in `url` with `${version}`.
-* The json output `requires` must be transformed into `propagetedBuildInputs`.
+* The json output `requirements` must be transformed into package `requirements`.
 * If `license` is `"MIT"`, it can be left out in the nix expression, as the builder defaults to that license.
 * Add yourself as maintainer in `meta.maintainers`.
 

pkgs/by-name/az/azure-cli/extensions-tool.py

···
     return max(versions, key=lambda e: parse(e["metadata"]["version"]), default=None)
 
 
-def processExtension(
+def find_extension_version(
     extVersions: dict,
     cli_version: Version,
     ext_name: Optional[str] = None,
     requirements: bool = False,
-) -> Optional[Ext]:
+) -> Optional[Dict[str, Any]]:
     versions = filter(_filter_invalid, extVersions)
     versions = filter(lambda v: _filter_compatible(v, cli_version), versions)
     latest = _get_latest_version(versions)
···
     if ext_name and latest["metadata"]["name"] != ext_name:
         return None
     if not requirements and "run_requires" in latest["metadata"]:
+        return None
+    return latest
+
+
+def find_and_transform_extension_version(
+    extVersions: dict,
+    cli_version: Version,
+    ext_name: Optional[str] = None,
+    requirements: bool = False,
+) -> Optional[Ext]:
+    latest = find_extension_version(extVersions, cli_version, ext_name, requirements)
+    if not latest:
         return None
 
     return _transform_dict_to_obj(latest)
···
         action=argparse.BooleanOptionalAction,
         help="whether to commit changes to git",
     )
+    parser.add_argument(
+        "--init",
+        action=argparse.BooleanOptionalAction,
+        help="whether you want to init a new extension",
+    )
     args = parser.parse_args()
     cli_version = parse(args.cli_version)
 
···
     assert index["formatVersion"] == "1"  # only support formatVersion 1
     extensions_remote = index["extensions"]
 
+    # init just prints the json of the extension version that matches the cli version.
+    if args.init:
+        if not args.extension:
+            logger.error("extension name is required for --init")
+            exit(1)
+
+        for ext_name, ext_versions in extensions_remote.items():
+            if ext_name != args.extension:
+                continue
+            ext = find_extension_version(
+                ext_versions,
+                cli_version,
+                args.extension,
+                requirements=True,
+            )
+            break
+        if not ext:
+            logger.error(f"Extension {args.extension} not found in index")
+            exit(1)
+
+        ext_translated = {
+            "pname": ext["metadata"]["name"],
+            "version": ext["metadata"]["version"],
+            "url": ext["downloadUrl"],
+            "hash": _convert_hash_digest_from_hex_to_b64_sri(ext["sha256Digest"]),
+            "description": ext["metadata"]["summary"].rstrip("."),
+            "license": ext["metadata"]["license"],
+            "requirements": ext["metadata"]["run_requires"][0]["requires"],
+        }
+        print(json.dumps(ext_translated, indent=2))
+        return
+
     if args.extension:
         logger.info(f"updating extension: {args.extension}")
 
         ext = Optional[Ext]
         for _ext_name, extension in extensions_remote.items():
-            extension = processExtension(
+            extension = find_and_transform_extension_version(
                 extension, cli_version, args.extension, requirements=True
             )
             if extension:
···
 
     extensions_remote_filtered = set()
     for _ext_name, extension in extensions_remote.items():
-        extension = processExtension(extension, cli_version, args.extension)
+        extension = find_and_transform_extension_version(
+            extension, cli_version, args.extension
+        )
         if extension:
             extensions_remote_filtered.add(extension)