Feature request: customizable auto-generated conversation titles

Problem

The VS Code extension now auto-generates conversation titles, which is great. But there's no way to influence how they're named.

For users who rely on slash commands (custom skills) to bootstrap different workstreams — e.g. /bq for BigQuery, /dash for dashboard work, /infra for DevOps — the auto-generated title doesn't reflect which context the conversation is operating in. You end up with a list of past conversations that all look similar and don't tell you at a glance what kind of agent you're talking to.

Proposed solution

Allow users to provide direction on how titles are generated. The most valuable signal would be incorporating the slash command (skill) used in the conversation, so titles might look like:

• [/bq] Fix orphaned cost row join
• [/dash] Add rep commission chart
• [/infra] Cloud function deploy pipeline

This could be implemented as:

• A setting or template string for title generation (e.g. "claude.titlePrefix": "slash-command")
• A hook that runs on title generation and can modify the result
• Simply detecting when a slash command is the first message and prepending it automatically

Any of these would work. The core need is: when scanning a list of past conversations, immediately know which workstream/context each one belongs to.