[FEATURE] Feature request: open a specific session in the sidebar (URI location param or sidebar.openSession command)

Preflight Checklist

• [x] I have searched existing requests and this feature hasn't been requested yet
• [x] This is a single feature request (not multiple features)

Problem Statement

External tools can ask the VS Code extension to open a specific session via vscode://anthropic.claude-code/open?session=<id>&prompt=<text>, but the handler unconditionally forwards to claude-vscode.primaryEditor.open, which opens in the editor column. There is no way to target the side bar with a session id:

claude-vscode.sidebar.open takes no arguments — it opens the side bar but cannot select a session.
claude-vscode.primaryEditor.open(session, prompt) takes a session id but is pinned to the editor column.
The extension exports no API from activate(), so a companion extension cannot bridge the gap either.
For users who keep Claude Code docked in the side bar, an external "jump to this session" integration has to either open a duplicate editor tab or give up.

Proposed Solution

Request — either one solves it:

Honour a location=sidebar (or preferredLocation) query parameter on the /open URI, or
Contribute a claude-vscode.sidebar.openSession(sessionId, prompt) command — the side bar equivalent of the existing primaryEditor.open.
Why it matters: without it, the only way to get this behaviour is patching the shipped bundle, which breaks on extension updates (2.1.226 → 2.1.227 changed the webview bootstrap's statement structure). A supported entry point would remove that entirely.

Version: 2.1.227, darwin-arm64

Alternative Solutions

_No response_

Priority

Critical - Blocking my work

Feature Category

Developer tools/SDK

Use Case Example

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Additional Context

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