[BUG] Clear Messages does not fully reset session in Agents/Pipelines

[epamLDadayan]

Title: Clear Messages does not fully reset session in Agents/Pipelines

Description:
Clicking Clear messages only wipes the UI. The same stream/session ID is reused, so a new input binds to the previous run/context. This causes failures or mixed results, especially after a pipeline has completed.

Steps to reproduce:

1. Open any Agent or Pipeline and run it to completion (or exchange a few messages).
2. Click Clear messages.
3. Send a new message/input.

Actual Result:

• New input uses the old stream/session ID.
• Pipeline may not start a fresh run or returns stale/mixed outputs.
• Recovery typically requires a full page reload.

Expected Result:

• Clear messages should fully reset conversation/session state (new stream/session ID, no prior context).
• Next input starts a clean run without needing a reload.

Notes (optional):

• Workaround: reload the page after clearing messages.

[epamLDadayan]

@HawkQing1 , @daniilmotsniy told that we need to send "Delete request" to clear conversation.

[HawkQing1]

@epamLDadayan it should be fixed on dev, please verify it.

[epamLDadayan]

@HawkQing1 this is not working for Pipelines from Configuration tab, as a differnt hook is used (pipeline hook) and for Run tab we are using agent hook.