Improve Session ID Visibility for Easier Recovery (make it visible on startup)

### Describe the feature or problem you'd like to solve

Display session ID prominently for easier identification and recovery after crashes

### Proposed solution

When the terminal freezes and needs to be force-closed, there's no way to disable Copilot gracefully. This means there's no session ID readily available to restore the session.

**Current behavior:**
- Session IDs are not visible or easily accessible during active use
- After a crash, multiple sessions exist with no clear way to distinguish between them
- Users must recall their starting prompt to identify the correct session
- Session IDs all look similar, making it difficult to identify which is which

**Expected behavior:**
- Session ID should be visible from the start of the session
- Users should be able to easily copy the session ID
- Sessions should be more distinguishable (e.g., show timestamp, first prompt preview, or a memorable identifier)

**Impact:**
- Time lost trying to locate the correct session after a crash
- Frustration when multiple sessions exist with no clear differentiation
- Risk of losing work context when the wrong session is restored

**Suggested improvements:**
1. Display the session ID in the UI header or status bar
2. Add a "Copy Session ID" button
3. Include additional metadata (timestamp, first prompt snippet) in the session list
4. Consider user-friendly session names or aliases

### Example prompts or workflows

Two ideas on where to show it:

_No response_

### Additional context

_No response_