Add --name flag for remote/background sessions

Feature Request

Problem

When launching multiple background/remote sessions with & or --remote, there's no way to give them a human-friendly name at creation time. The only option is /rename after the session starts, which doesn't work well for background sessions since you're not interacting with them directly.

When working on multiple features in parallel (e.g., building a leads page, fixing billing, refactoring auth), all background sessions show up with auto-generated names or truncated prompts, making it hard to identify and switch between them.

Proposed Solution

Add a --name (or --title) flag that sets the session's display name at creation:

# From CLI
claude --remote --name "leads-page" "Build the leads list page with filters"

# From interactive session (& syntax)
& --name leads-page Build docs/features/leads-page.md

The name would appear in:

• /tasks output
• /resume session picker
• Claude.ai web session list
• Claude iOS app session list

Why This Matters

Power users who run multiple background sessions in parallel need a quick way to identify sessions by feature/task name. Currently:

1. Launch & Build the leads page → session shows truncated prompt
2. Launch & Fix the billing webhook → another truncated prompt
3. /tasks shows two sessions that are hard to distinguish at a glance

With --name:

1. & --name leads-page Build the leads page → clearly labeled
2. & --name billing-fix Fix the billing webhook → clearly labeled
3. /tasks shows "leads-page" and "billing-fix" — instant recognition

Alternatives Considered

• /rename after launch: Doesn't work for background sessions since you're not in the session to run the command
• Shell wrapper functions: Can print the name locally but can't actually tag the remote session
• --session-id: Requires a UUID, not human-friendly

Additional Context

This would significantly improve the multi-session workflow for developers who use & to parallelize feature work across multiple background agents.