Fix resolving review threads from the webview

[alexr00]

No description provided.

[Copilot]

Pull request overview

This PR fixes resolving/unresolving review threads from the PR timeline webview by ensuring the UI targets the correct GraphQL review thread when a single review contains comments across multiple threads.

Changes:

• Add threadId (GraphQL review thread node ID) to IComment when parsing comments from GraphQL review threads.
• Track resolve/unresolve permissions per review thread (map keyed by thread GraphQL ID) on each ReviewEvent.
• Update the webview timeline to group comments by threadId (falling back to path+position) and resolve/unresolve the specific thread for that group.

Show a summary per file

File	Description
webviews/components/timeline.tsx	Groups review comments by threadId and resolves the correct thread per rendered comment group.
src/github/utils.ts	Propagates GraphQL review thread ID into parsed IComment objects.
src/github/pullRequestModel.ts	Populates a per-review map of thread resolve info so the webview can target the correct thread.
src/common/timelineEvent.ts	Updates ReviewEvent shape to expose reviewThreads (threadId → resolve info).
src/common/comment.ts	Extends IComment with optional threadId to associate comments with their review thread.

Copilot's findings

• Files reviewed: 5/5 changed files
• Comments generated: 0