chore: example to add Mapped

[asukaminato0721]

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Summary

#40373

Screenshots

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Checklist

• This change requires a documentation update, included: Dify Document
• I understand that this PR may be closed in case there was no previous discussion or issues. (This doesn't apply to typos!)
• I've added a test for each change that was introduced, and I tried as much as possible to make a single atomic change.
• I've updated the documentation accordingly.
• I ran make lint && make type-check (backend) and cd web && pnpm exec vp staged (frontend) to appease the lint gods

[github-actions]

Pyrefly Diff

base → PR

--- /tmp/pyrefly_base.txt	2026-08-09 12:26:45.808829520 +0000
+++ /tmp/pyrefly_pr.txt	2026-08-09 12:26:32.029789225 +0000
@@ -632,6 +632,18 @@
    --> tests/integration_tests/workflow/test_response_stream_filter_pause_resume_integration.py:113:14
 ERROR Argument `Literal['image']` is not assignable to parameter `value` with type `IconType | SQLCoreOperations[IconType | None] | None` in function `sqlalchemy.orm.base.Mapped.__set__` [bad-argument-type]
    --> tests/test_containers_integration_tests/controllers/web/test_site.py:115:26
+ERROR Argument `None` is not assignable to parameter `value` with type `SQLCoreOperations[str] | str` in function `sqlalchemy.orm.base.Mapped.__set__` [bad-argument-type]
+   --> tests/test_containers_integration_tests/controllers/web/test_site.py:204:33
+ERROR Argument `None` is not assignable to parameter `value` with type `SQLCoreOperations[str] | str` in function `sqlalchemy.orm.base.Mapped.__set__` [bad-argument-type]
+   --> tests/test_containers_integration_tests/controllers/web/test_site.py:206:21
+ERROR Argument `None` is not assignable to parameter `value` with type `SQLCoreOperations[str] | str` in function `sqlalchemy.orm.base.Mapped.__set__` [bad-argument-type]
+   --> tests/test_containers_integration_tests/controllers/web/test_site.py:207:32
+ERROR Argument `None` is not assignable to parameter `value` with type `SQLCoreOperations[str] | str` in function `sqlalchemy.orm.base.Mapped.__set__` [bad-argument-type]
+   --> tests/test_containers_integration_tests/controllers/web/test_site.py:208:28
+ERROR Argument `None` is not assignable to parameter `value` with type `SQLCoreOperations[str] | str` in function `sqlalchemy.orm.base.Mapped.__set__` [bad-argument-type]
+   --> tests/test_containers_integration_tests/controllers/web/test_site.py:209:26
+ERROR Argument `None` is not assignable to parameter `value` with type `SQLCoreOperations[str] | str` in function `sqlalchemy.orm.base.Mapped.__set__` [bad-argument-type]
+   --> tests/test_containers_integration_tests/controllers/web/test_site.py:210:31
 ERROR Argument `SimpleNamespace` is not assignable to parameter `webapp_settings` with type `WebAppSettings | None` in function `controllers.web.wraps._validate_user_accessibility` [bad-argument-type]
   --> tests/test_containers_integration_tests/controllers/web/test_wraps.py:77:33
 ERROR Argument `SimpleNamespace` is not assignable to parameter `webapp_settings` with type `WebAppSettings | None` in function `controllers.web.wraps._validate_user_accessibility` [bad-argument-type]

[github-actions]

Pyrefly Type Coverage

Metric	Base	PR	Delta
Type coverage	58.26%	58.26%	0.00%
Strict coverage	57.84%	57.84%	0.00%
Typed symbols	38,287	38,287	0
Untyped symbols	27,627	27,627	0
Modules	3144	3144	0