docs(changelog): steer subscribes before sending; dashboard toolchain refresh

[indykish]

New changelog entry: the CLI steer turn subscribes to the live tail (established subscription) before sending; dashboard toolchain refresh clears the Next.js high advisories on TypeScript 7.

Pairs with agentsfleet PR for the steer subscribe-first fix.

🤖 Generated with Claude Code

Greptile Summary

Adds a July 31 changelog update covering:

• Subscribe-before-send behavior and cancellation/stream cleanup fixes for agentsfleet steer.
• A dashboard toolchain refresh addressing three Next.js security advisories and adopting the TypeScript 7 compiler.

Confidence Score: 4/5

The documentation change is safe to merge on or after July 31, but merging earlier would prematurely publish the release announcement.

The MDX follows established changelog structure, with the only concern being that its future-dated entry is rendered immediately rather than scheduled.

Files Needing Attention: changelog.mdx

Important Files Changed

Filename	Overview
changelog.mdx	Adds a structurally valid changelog entry, but its future date requires holding publication until July 31 to avoid announcing the fixes early.

Prompt To Fix All With AI

### Issue 1
changelog.mdx:10
**Future-dated release announcement**

The changelog publishes entries immediately in source order, so merging this entry before July 31 announces the CLI and dashboard fixes before their stated release date; hold publication until that date or use the intended release date.

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For each issue above, determine whether it is valid and should be fixed. If so, fix it directly.

_{Reviews (1): Last reviewed commit: "docs(changelog): steer subscribes before..." | Re-trigger Greptile}

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