view goose sessions in human friendly format

**What problem would this solve?**
goose lets you export sessions to markdown, json, yaml but none of these formats lets me scan through a session quickly. its not human friendly. this matters even more when `goose` is used over ACP in buzz since buzz doesn't show intermediate tool calls and sometimes, you wanna inspect a session afterwards (eg. it took longer than you expected).

**What would a good outcome look like?**
Example pi session: https://pi.dev/session/#b23f2459599f8439327f65c90ee95d06

**Possible approaches**
Put in a PR here: https://github.com/aaif-goose/goose/pull/11977 (see screenshots in the PR)

**Additional context**
Add any other context or screenshots about the feature request here.

- [x] I have verified this does not duplicate an existing feature request

Do not begin implementation until the issue reaches **Ready** on the [Goose Issues board](https://github.com/orgs/aaif-goose/projects/1).

Review the linked PR #11977 for screenshots and context on the human-friendly session view. Examine the existing session export code (likely in a CLI module) that outputs markdown, JSON, and YAML. Understand the session data structure to format it for quick scanning, similar to the pi.dev example. Implement a new output format, ensuring it integrates with the existing export commands.

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