Feature Request: Show timestamp on user prompts

Feature Request

Description:
Display a timestamp when the user submits a prompt, showing when each message was sent.

Use Cases:

• Track how long you've been in a session
• Context when reading back through a conversation history
• Know when a session started vs resumed
• Helpful for wrap-up/progress notes ("what time did I start this?")

Suggested Implementation:

• Could be displayed in the gutter next to the prompt
• Or in a subtle response header
• Format: HH:MM (24hr) or configurable

Why it matters:
Currently there's no visual indication of time passing during a session. When you step away and come back, or when reviewing a long conversation, timestamps would provide useful context.

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Submitted via Claude Code session