Fix mypy compatibility and add 5.0 conformance tests

- Qualify bare "object" as builtins.object in bpy.types to avoid shadowing
  by Context.object and similar properties
- Use _Sequence alias import to fix mypy "collections.abc.Sequence not defined"
- Filter out variables that clash with submodule re-exports (e.g. bpy.app)
- Add 5.0 conformance tests from Blender 5.0 mathutils documentation

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

generate_stubs.py

@@ -600,7 +600,9 @@ def generate_types_stub(
     if "Sequence[" in all_type_strs:
         # Use fully qualified import to avoid shadowing by bpy.types.Sequence
         # (the video sequencer strip type)
+        imports.append("import collections")
         imports.append("import collections.abc")
+        imports.append("from collections.abc import Sequence as _Sequence")
 
     parts: list[str] = []
     if doc:
@@ -629,10 +631,14 @@ def generate_types_stub(
     result = "\n".join(parts)
     class_names = {s["name"] for s in structs}
     result = strip_self_module_prefix(result, "bpy.types", class_names)
-    # Qualify all bare Sequence[ references to avoid shadowing by bpy.types.Sequence
-    result = re.sub(
-        r"(?<!\.)(?<!\w)\bSequence\[", "collections.abc.Sequence[", result
-    )
+    # Replace bare Sequence[ with _Sequence[ to avoid shadowing by bpy.types.Sequence
+    result = re.sub(r"(?<!\.)(?<!\w)\bSequence\[", "_Sequence[", result)
+    # Qualify bare "object" in type annotations to avoid shadowing by
+    # properties named "object" (e.g. Context.object: Object).
+    result = re.sub(r"(?<=: )object\b", "builtins.object", result)
+    result = re.sub(r"(?<=\| )object\b", "builtins.object", result)
+    result = re.sub(r"(?<=\[)object\b", "builtins.object", result)
+    result = re.sub(r"(?<=-> )object\b", "builtins.object", result)
     return prune_unused_imports(result)
 
 
@@ -755,11 +761,13 @@ def generate_module_stub(
         parts.append('_T = TypeVar("_T")')
         parts.append("")
 
-    # Variables
+    # Variables (skip those that clash with submodule re-exports)
+    sub_names = set(submodule_names or [])
     if module_data["variables"]:
         parts.append("")
         for var in module_data["variables"]:
-            parts.append(generate_variable_stub(var))
+            if var["name"] not in sub_names:
+                parts.append(generate_variable_stub(var))
 
     # Functions
     for func in module_data["functions"]: