fix(cli): count aliases in removal confirmation command count (#2017)

The "N commands from AI agent" line in the removal confirmation was
derived from len(manifest.commands) which counts command entries, not
registered names. Extensions with aliases therefore showed the wrong
count (e.g. 1 instead of 2 for a command with one alias).

Use the registry's registered_commands dict instead — summing actual
registered names across all agents — so the count reflects what will
actually be removed.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

Author: iamaeroplane

src/specify_cli/__init__.py

@@ -3123,9 +3123,13 @@ def extension_remove(
     extension_id, display_name = _resolve_installed_extension(extension, installed, "remove")
 
     # Get extension info for command and skill counts
-    ext_manifest = manager.get_extension(extension_id)
-    cmd_count = len(ext_manifest.commands) if ext_manifest else 0
     reg_meta = manager.registry.get(extension_id)
+    # Count total registered commands across all agents (includes aliases)
+    registered_commands = reg_meta.get("registered_commands", {}) if reg_meta else {}
+    cmd_count = sum(
+        len(names) for names in registered_commands.values()
+        if isinstance(names, list)
+    )
     raw_skills = reg_meta.get("registered_skills") if reg_meta else None
     skill_count = len(raw_skills) if isinstance(raw_skills, list) else 0