Render Markdown links without duplicate destinations

[mochow13]

Problem

The REPL's Markdown renderer prints both a link's label and destination. For example:

[internal/cli/repl/repl.go:413](/internal/cli/repl/repl.go#L413)

is displayed with the source location followed by the duplicate target path.

Desired behavior

• Relative repository source references and anchors should display their label only.
• External http and https links should remain clickable in terminals that support OSC 8 hyperlinks, without printing a duplicate destination.
• Bare URLs should retain their current behavior.

Suggested approach

Update the REPL Markdown rendering layer to classify Markdown link destinations before rendering:

Destination	Rendering
Relative path or #anchor	Display label only
http:// or https://	Render label as an OSC 8 terminal hyperlink

Avoid a broad regex replacement that would strip or break ordinary external links. Add focused tests for a relative source reference and an external URL.