[Feat] feat: add AI‑assisted workflow‑generation copilot

### Self Checks

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### 1. Is this request related to a challenge you're experiencing? Tell me about your story.

**Feature Description**
Add a standalone workspace for AI‑assisted workflow creation. Users are allowed to iterate and fine‑tune canvas workflows via multi‑round natural‑language conversations. This delivers the full AI‑driven orchestration workflow, covering one‑click generation, repeated adjustments and detailed optimization.
**Modification Scope**
Build a side panel serving as the entry point for the AI‑assisted workflow‑generation workspace and conversation interaction.
Preserve multi‑turn‑dialogue context and support incremental workflow edits based on the existing canvas content.
Implement ID mapping adaptation for nodes already rendered on the canvas.
Fix syntax errors within workflow‑generator unit‑tests to make sure all CI checks pass.
**Acceptance Criteria**
The AI‑assisted workflow‑generation workspace loads and renders correctly
Initial workflow generation and subsequent iterative edits through multiple rounds of chat are functional
Unit‑test, linter and pre‑commit checks are all passed
Chat‑session context can be reused continuously, and every iterative modification takes effect on the canvas properly

### 2. Additional context or comments

_No response_

### 3. Can you help us with this feature?

- [x] I am interested in contributing to this feature.

Start at the existing workflow-generation workspace and canvas side-panel entry points; the issue does not name specific files. Trace how canvas nodes are represented and how workflow-generator unit tests are organized, then verify generation, multi-round edits, ID mapping, and canvas updates. Run the workflow-generator unit tests plus the repository's linter and pre-commit checks.

Written by the indexing model from the issue text.