Add JSON comparison to demonstrate token efficiency

[Copilot]

Added Siren-style JSON representation of the albums example to quantify Jiron's token efficiency advantage over traditional API formats.

Changes

• examples/albums.json - Siren-compliant JSON with properties expanded into name/value object pairs
• README.md - Added JSON example and token usage comparison table after HTML example

Token Usage

Jiron (pug):  918 chars
JSON:       1,065 chars (+16%)
HTML:       1,434 chars (+56%)

The JSON demonstrates how Siren's object-based property model ({"name": "artist", "value": "Pink Floyd"}) is more verbose than Jiron's inline syntax (li.property.artist Pink Floyd), even when representing identical hypermedia semantics.

Original prompt

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This section details on the original issue you should resolve

<issue_title>add json comparison</issue_title>
<issue_description>show what it would look like to see the example code as json, expanding attributes into a child object to compare token usage</issue_description>

Comments on the Issue (you are @copilot in this section)

• Fixes add json comparison #5

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