Pin sessions to top of Session History in VSCode extension

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

In the VSCode extension, Session History only supports time-based
filtering (Today, Last 7 days, etc.). For long-running projects
where I return to the same session over weeks, important sessions
get buried under newer ones and there's no way to keep them
accessible at the top.
זW

Proposed Solution

Add a "Pin" action when hovering over a session in Session History,
next to the existing Rename/Delete actions. Pinned sessions appear
in a dedicated "Pinned" group at the top of the history list,
above the time-based groups (Today, Last 7 days, etc.).

Clicking Pin again on a pinned session unpins it.

Alternative Solutions

Currently I rename sessions with descriptive prefixes to make them
easier to spot, but they still get buried as new sessions push them
down. Time-based filtering doesn't help because the sessions I care
about may be weeks old.

Priority

Low - Nice to have

Feature Category

Interactive mode (TUI)

Use Case Example

Example scenario:

1. I'm a real estate broker building 3 long-running projects

(CRM, marketing automation, SEO site) over several months

1. Each project has a dedicated session I return to weekly
2. With pinning, I'd pin those 3 sessions to the top
3. New short-lived sessions (one-off questions, experiments)

live below in the time-based groups

1. I always know where to find my main work without scrolling

or searching

Additional Context

Similar to how VSCode itself pins tabs, or how Slack and Discord
allow pinning conversations to the top of the list.