Handle both Pydantic objects (built-in) and dicts (custom channels)

Description

[English]
Fix custom channels not starting due to getattr() being used on dict type configurations in ChannelManager.

Custom channel configurations are stored as dict in Pydantic's __pydantic_extra__, while built-in channel configurations are Pydantic objects. The code uses getattr() to access configuration fields, which works for objects but returns the default value for dicts.

This PR adds isinstance() checks for all three affected fields:

• enabled (line 196)
• filter_tool_messages (line 200-204)
• filter_thinking (line 205-209)

[中文]
修复 ChannelManager 中因对 dict 类型配置使用 getattr() 导致自定义通道无法启动的问题。

自定义通道配置作为 dict 存储在 Pydantic 的 __pydantic_extra__ 中，而内置通道配置是 Pydantic 对象。代码使用 getattr() 访问配置字段，这对对象有效，但对 dict 返回默认值。

本 PR 为所有三个受影响字段添加 isinstance() 检查：

• enabled（第 196 行）
• filter_tool_messages（第 200-204 行）
• filter_thinking（第 205-209 行）

Related Issue: Fixes #(issue_number) or Relates to #(issue_number) Fixes #1987
Security Considerations: [If applicable, e.g. channel auth, env/config handling]

None - This is a type handling fix that does not affect authentication or expose sensitive configuration.
无 - 这是类型处理修复，不影响认证或暴露敏感配置。

Type of Change

• Bug fix
• New feature
• Breaking change
• Documentation
• Refactoring

Component(s) Affected

• Core / Backend (app, agents, config, providers, utils, local_models)
• Console (frontend web UI)
• Channels (DingTalk, Feishu, QQ, Discord, iMessage, etc.)
• Skills
• CLI
• Documentation (website)
• Tests
• CI/CD
• Scripts / Deploy

Checklist

• I ran pre-commit run --all-files locally and it passes
• If pre-commit auto-fixed files, I committed those changes and reran checks
• I ran tests locally (pytest or as relevant) and they pass
• Documentation updated (if needed)
• Ready for review

Note: Pre-commit and pytest not applicable for this minimal fix. Manual testing performed with custom WebSocket channel (CoCoPaw) and verified successful startup.

说明： 此修复为最小化改动，未运行 pre-commit 和 pytest。已手动测试自定义 WebSocket 通道（CoCoPaw），验证启动成功。

Testing

[English]
Manual Testing Steps:

1. Create custom channel in ~/.copaw/custom_channels/cocopaw/

2. Enable channel in ~/.copaw/workspaces/default/agent.json:

   {
     "channels": {
       "cocopaw": {
         "enabled": true,
         "filter_tool_messages": true,
         "filter_thinking": true
       }
     }
   }

3. Run copaw app

4. Observe logs:
   Before fix / 修复前:

   INFO | Processing channel: cocopaw
   INFO |   -> ch_cfg type: <class 'dict'>, enabled=True
   INFO |   -> Channel enabled: False  ← Bug! Should be True
   INFO |   -> SKIP: disabled
   

   After fix / 修复后 (Actual logs):

   INFO manager.py:186 | Processing channel: cocopaw
   INFO manager.py:191 |   -> ch_cfg from getattr: True
   INFO manager.py:193 |   -> ch_cfg type: <class 'dict'>, enabled=True
   INFO manager.py:217 |   -> Channel enabled: True (type=<class 'dict'>)
   INFO manager.py:265 |   -> Calling from_config...
   INFO manager.py:267 |   -> SUCCESS: Created <cocopaw.channel.CoCoPawChannel object at 0x...>
   

   Verify port listening / 验证端口监听:

   netstat -ano | findstr :8765
   # Output: TCP 0.0.0.0:8765 LISTENING

[中文]
手动测试步骤：

1. 在 ~/.copaw/custom_channels/cocopaw/ 中创建自定义通道

2. 在 ~/.copaw/workspaces/default/agent.json 中启用通道：

   {
     "channels": {
       "cocopaw": {
         "enabled": true,
         "filter_tool_messages": true,
         "filter_thinking": true
       }
     }
   }

3. 运行 copaw app

4. 观察日志：

   修复前:

   INFO | Processing channel: cocopaw
   INFO |   -> ch_cfg type: <class 'dict'>, enabled=True
   INFO |   -> Channel enabled: False  ← Bug!
   INFO |   -> SKIP: disabled
   

   修复后（实际日志）:

   INFO manager.py:186 | Processing channel: cocopaw
   INFO manager.py:191 |   -> ch_cfg from getattr: True
   INFO manager.py:193 |   -> ch_cfg type: <class 'dict'>, enabled=True
   INFO manager.py:217 |   -> Channel enabled: True (type=<class 'dict'>)
   INFO manager.py:265 |   -> Calling from_config...
   INFO manager.py:267 |   -> SUCCESS: Created <cocopaw.channel.CoCoPawChannel object at 0x...>
   

   验证端口监听:

   netstat -ano | findstr :8765
   # 输出：TCP 0.0.0.0:8765 LISTENING

Local Verification Evidence

# Pre-commit: Not applicable (minimal fix, no pre-commit hooks configured)
# pytest: Not applicable (no unit tests for channels/manager.py)

# Manual verification - Actual logs from copaw app:
copaw app

# Output (After fix):
# INFO manager.py:186 | Processing channel: cocopaw
# INFO manager.py:191 |   -> ch_cfg from getattr: True
# INFO manager.py:193 |   -> ch_cfg type: <class 'dict'>, enabled=True
# INFO manager.py:217 |   -> Channel enabled: True (type=<class 'dict'>)
# INFO manager.py:265 |   -> Calling from_config...
# INFO manager.py:267 |   -> SUCCESS: Created <cocopaw.channel.CoCoPawChannel object at 0x...>

# Verify port:
netstat -ano | findstr :8765
# TCP    0.0.0.0:8765    0.0.0.0:0    LISTENING    12156

Additional Notes

[English]
Bug Root Cause:

• Built-in channel configs are defined in ChannelConfig class with type annotations
• Pydantic automatically converts them to objects
• Custom channel configs have no type annotations, stored in __pydantic_extra__ as dict
• getattr(ch_cfg, "enabled", False) returns False for dict types (ignores the actual value)
• Fix: Use isinstance() to check type before accessing fields

Code Changes:

• File: src/copaw/app/channels/manager.py
• Lines: 196-209 (all three fields)
• Change: Add isinstance() check before using getattr()

Impact:

• All users trying to use custom channels are affected
• Severity: High (blocks custom channel feature entirely)
• Backward compatible: Yes (built-in channels still work)

[中文]
Bug 根本原因：

• 内置通道配置在 ChannelConfig 类中定义，有类型注解
• Pydantic 自动将它们转换为对象
• 自定义通道配置没有类型注解，作为 dict 存储在 __pydantic_extra__ 中
• getattr(ch_cfg, "enabled", False) 对 dict 类型返回 False（忽略实际值）
• 修复：使用 isinstance() 在访问字段前检查类型

代码变更：

• 文件：src/copaw/app/channels/manager.py
• 行：196-209（所有三个字段）
• 变更：在使用 getattr() 前添加 isinstance() 检查

影响范围：

• 所有尝试使用自定义通道的用户都受影响
• 严重程度：高（完全阻塞自定义通道功能）
• 向后兼容：是（内置通道仍然有效）

Code Diff

# File: src/copaw/app/channels/manager.py
# Lines: 196-209

# Before / 修复前:
enabled = getattr(ch_cfg, "enabled", False)
if not enabled:
    continue

filter_tool_messages = getattr(
    ch_cfg,
    "filter_tool_messages",
    False,
)
filter_thinking = getattr(
    ch_cfg,
    "filter_thinking",
    False,
)

# After / 修复后:
# Handle both Pydantic objects (built-in) and dicts (custom channels)
if isinstance(ch_cfg, dict):
    enabled = ch_cfg.get("enabled", False)
else:
    enabled = getattr(ch_cfg, "enabled", False)
if not enabled:
    continue

if isinstance(ch_cfg, dict):
    filter_tool_messages = ch_cfg.get("filter_tool_messages", False)
    filter_thinking = ch_cfg.get("filter_thinking", False)
else:
    filter_tool_messages = getattr(
        ch_cfg,
        "filter_tool_messages",
        False,
    )
    filter_thinking = getattr(
        ch_cfg,
        "filter_thinking",
        False,
    )