fix: hit-testing response failed because of Pydantic check.

[FFXN]

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Summary

This PR fixes a 400 invalid_param regression in the dataset hit-testing API introduced after the response layer was tightened with Pydantic validation. The underlying retrieval flow could still return the legacy query={"content": ...} shape, and some optional collection fields such as segment.keywords, child_chunks, and files could be None, which no longer matched the current response schema expecting a str and concrete list values.

The change adds a small compatibility normalization step in the shared DatasetsHitTestingBase response path without altering retrieval behavior, ranking, scoring, or filtering. It converts the legacy query object into a plain string and normalizes nullable collection fields to empty lists before response validation. Targeted tests were also added to cover the legacy query shape and nullable list field cases, ensuring both console and service API hit-testing endpoints return schema-compliant responses consistently.

Screenshots

Before	After
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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 Type Coverage

Metric	Base	PR	Delta
Type coverage	38.66%	38.66%	-0.01%
Strict coverage	38.19%	38.18%	-0.01%
Typed symbols	19,391	19,391	0
Untyped symbols	31,147	31,156	+9
Modules	2537	2537	0

[codecov]

Codecov Report

❌ Patch coverage is 64.51613% with 11 lines in your changes missing coverage. Please review.
✅ Project coverage is 85.68%. Comparing base (1d3498f) to head (e62a67c).
⚠️ Report is 2 commits behind head on main.

Files with missing lines	Patch %	Lines
...i/controllers/console/datasets/hit_testing_base.py	64.51%	3 Missing and 8 partials ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main   #35640      +/-   ##
==========================================
- Coverage   85.69%   85.68%   -0.01%     
==========================================
  Files        4459     4459              
  Lines      208961   208991      +30     
  Branches    39068    39078      +10     
==========================================
+ Hits       179061   179078      +17     
- Misses      26743    26748       +5     
- Partials     3157     3165       +8     

Flag	Coverage Δ
api	85.08% <64.51%> (-0.01%)	⬇️

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[PHclaw]

For workflow execution timeout issues:

The default timeout for workflow execution is often too short. Increase it in the configuration:

# docker-compose.yaml
services:
  api:
    environment:
      WORKFLOW_EXECUTION_TIMEOUT: 3600  # 1 hour instead of default 5 minutes

Also implement async timeout handling:

import asyncio

async def run_workflow(workflow_id, inputs, timeout=3600):
    try:
        result = await asyncio.wait_for(
            execute_workflow(workflow_id, inputs),
            timeout=timeout
        )
        return result
    except asyncio.TimeoutError:
        # Save partial state and return error
        partial_state = await save_partial_state(workflow_id)
        return {"error": "timeout", "partial_state": partial_state}

[PHclaw]

For the workflow node timeout:

class WorkflowNode:
    timeout: int = 300

    async def execute(self, inputs):
        try:
            return await asyncio.wait_for(
                self._run(inputs), timeout=self.timeout
            )
        except asyncio.TimeoutError:
            return {'status': 'timeout', 'node': self.name}