[Docs]: api.md MessageItem.content links to non-existent #addmessage anchor

[Fearvox]

Area: documentation

Page or file: docs/api.md (line 796)

What should be improved?

In the buffered-message table, the content row links [MessageItem.content](#addmessage). The fragment #addmessage does not correspond to any heading or HTML anchor anywhere in docs/api.md, so the link is dead — clicking it scrolls nowhere.

Every other MessageItem cross-reference in the same file uses #messageitem (lines 21 and 491), which matches the ### MessageItem heading at line 198.

Steps to reproduce

1. Open docs/api.md on GitHub (rendered Markdown).
2. Scroll to the buffered-message field table (around line 796).
3. Click the MessageItem.content link in the content row.
4. Observe the page does not scroll to any section (#addmessage is not a real anchor).
5. Confirm: grep -niE '^#+ .*addmessage' docs/api.md returns nothing.

Expected vs actual

• Expected: the link resolves to the ### MessageItem heading (line 198), slug #messageitem, consistent with lines 21 and 491.
• Actual: the link points to #addmessage, a dead anchor.

Environment

• Repo: EverMind-AI/EverOS
• File: docs/api.md
• Commit: 306dcfe (upstream/main as filed)
• Renderer: GitHub Markdown / any anchor-following Markdown viewer

Suggested wording or structure

Change [MessageItem.content](#addmessage) to [MessageItem.content](#messageitem).

A fix is staged at https://github.com/Fearvox/EverOS/pull/new/proofstorm/r1-doc-dead-xrefs.