feat(api): add sandbox info endpoint for Agent App conversations

[linw1995]

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Summary

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	2026-07-03 09:29:28.710724227 +0000
+++ /tmp/pyrefly_pr.txt	2026-07-03 09:29:20.054657448 +0000
@@ -7044,13 +7044,13 @@
 ERROR Argument `_FakeWriteSession` is not assignable to parameter `session` with type `scoped_session[Unknown]` in function `services.agent_app_feature_service.AgentAppFeatureConfigService.update_features` [bad-argument-type]
    --> tests/unit_tests/services/test_agent_app_feature_service.py:102:21
 ERROR Object of class `FromClause` has no attribute `create` [missing-attribute]
-   --> tests/unit_tests/services/test_agent_app_sandbox_service.py:151:5
+   --> tests/unit_tests/services/test_agent_app_sandbox_service.py:166:5
 ERROR Object of class `FromClause` has no attribute `drop` [missing-attribute]
-   --> tests/unit_tests/services/test_agent_app_sandbox_service.py:156:5
+   --> tests/unit_tests/services/test_agent_app_sandbox_service.py:171:5
 ERROR Object of class `object` has no attribute `session_snapshot` [missing-attribute]
-   --> tests/unit_tests/services/test_agent_app_sandbox_service.py:244:12
+   --> tests/unit_tests/services/test_agent_app_sandbox_service.py:259:12
 ERROR Object of class `object` has no attribute `session_snapshot` [missing-attribute]
-   --> tests/unit_tests/services/test_agent_app_sandbox_service.py:277:12
+   --> tests/unit_tests/services/test_agent_app_sandbox_service.py:292:12
 ERROR Argument `SimpleNamespace` is not assignable to parameter `version` with type `AgentConfigDraft | AgentConfigSnapshot` in function `services.agent_config_service.AgentConfigTarget.__init__` [bad-argument-type]
   --> tests/unit_tests/services/test_agent_config_service.py:69:17
 ERROR Object of class `FromClause` has no attribute `create` [missing-attribute]

[github-actions]

Pyrefly Type Coverage

Metric	Base	PR	Delta
Type coverage	52.30%	52.30%	+0.01%
Strict coverage	51.81%	51.82%	+0.01%
Typed symbols	32,016	32,027	+11
Untyped symbols	29,477	29,478	+1
Modules	2970	2970	0

[codecov]

Codecov Report

❌ Patch coverage is 95.23810% with 2 lines in your changes missing coverage. Please review.
✅ Project coverage is 85.29%. Comparing base (5622e8f) to head (5d5af52).
⚠️ Report is 7 commits behind head on main.

Files with missing lines	Patch %	Lines
api/services/agent_app_sandbox_service.py	88.88%	1 Missing and 1 partial ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main   #38390      +/-   ##
==========================================
- Coverage   85.29%   85.29%   -0.01%     
==========================================
  Files        4992     4993       +1     
  Lines      264162   264263     +101     
  Branches    50126    50136      +10     
==========================================
+ Hits       225309   225394      +85     
- Misses      34434    34448      +14     
- Partials     4419     4421       +2     

Flag	Coverage Δ
api	85.52% <95.23%> (-0.01%)	⬇️
dify-ui	94.93% <ø> (ø)
web	84.86% <ø> (+<0.01%)	⬆️

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