feat!: show the username first in USER_INFO text

[lukecotter]

📝 Overview

The USER_INFO event text was 005000000000AAA user@example.com. The id came first, but a reader looks for the username.

The text is now user@example.com : 005000000000AAA. A line with no username still gives the id alone.

🛠️ Changes

• USER_INFO text puts username before userId — the username is what a reader scans for; the id is a lookup key.
• The separator is ' : ', not a space — it matches the other catalog text rules.
• A test asserts the full text — before, no test checked it.

🧩 Type of change

• 🐛 Bug fix — fixes an issue
• ✨ Feature — adds new functionality
• ♻️ Refactor — no behaviour change
• ⚡ Performance
• 📝 Docs
• 🔧 Chore — tooling, CI, deps
• 💥 Breaking change

🔗 Related issues

N/A

✅ Checklist

• Tests added/updated
• pnpm run ci passes locally
• Changeset added (pnpm changeset) if this affects the published package
• Docs updated if behaviour or the public API changed

[codspeed]

Merging this PR will improve performance by 11.67%

⚠️ Different runtime environments detected

Some benchmarks with significant performance changes were compared across different runtime environments,
which may affect the accuracy of the results.

Open the report in CodSpeed to investigate

⚡ 1 improved benchmark
✅ 5 untouched benchmarks

Performance Changes

	Mode	Benchmark	BASE	HEAD	Efficiency
⚡	Memory	parse_19kb	212 KB	189.8 KB	+11.67%

Tip

Curious why performance improved? Comment @codspeedbot explain why performance improved on this PR, or directly use the CodSpeed MCP with your agent.

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_{Comparing feat/user-info-text (40e5f5d) with main (55427c4)}