feat: continue tool calls after rejection

[uinstinct]

Description

Continue streaming when a tool call is rejected. This PR introduces an experimental setting which will resume tool calls. It will skip the tool call if not necessary otherwise will try another approach.

resolves CON-2844

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Checklist

• [] I've read the contributing guide
• [] The relevant docs, if any, have been updated or created
• [] The relevant tests, if any, have been updated or created

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feat.mp4

Tests

[ What tests were added or updated to ensure the changes work as expected? ]

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Summary by cubic

Enable continuing the conversation after a tool call is rejected. Adds an opt-in setting that treats canceled tool calls as complete and resumes streaming (CON-2844).

• New Features
  • New UI setting: “Stream after tool rejection” (default off). Stored as ui.continueAfterToolRejection and added to shared config/types.
  • On cancel, appends a tool message (“User skipped the tool call”) and a “Tool Call Rejected” context item, then auto-continues the LLM response.
  • Tool-call completion logic considers “canceled” as done when the setting is enabled, so chats don’t get stuck.

[RomneyDa]

See comments!