docs: document self-hosted Gitea and its MCP tooling for agents

Make sure AI agents know this project is hosted on a self-hosted Gitea
instance rather than GitHub, and that mcp__angel__* MCP tools (with no
Projects API) are available for interacting with it.

AGENTS.md

@@ -249,6 +249,27 @@ against the live API doesn't exist yet.
   you test multiple identities/accounts side by side. Never enable this
   outside local development.
 
+## Gitea
+
+- This project is hosted on a self-hosted **Gitea** instance at
+  `gitea.inventory-plus-plus.com` (repo:
+  `angel/inventory-plus-plus`), not GitHub - the `origin` remote points at
+  it over SSH. Issues, pull requests, wiki, and CI (Gitea Actions - see the
+  Tests badge at the top of `README.md`) all live there rather than on
+  GitHub, even though the tooling/workflow (Actions YAML, PR-based review)
+  looks GitHub-shaped.
+- A Gitea MCP server is available in agent sessions (tools prefixed
+  `mcp__angel__...` - e.g. `issue_read`/`issue_write`,
+  `pull_request_read`/`pull_request_write`,
+  `list_pull_requests`/`list_issues`, `list_branches`, `wiki_read`/
+  `wiki_write`) for reading/managing issues, PRs, branches, releases, and
+  the wiki without shelling out to `git`/`gh`. There is no GitHub CLI
+  (`gh`) equivalent here - use these MCP tools or `git` directly instead.
+- The Gitea MCP server has **no Projects API** - it cannot read or modify
+  Gitea Project boards. Don't attempt to automate Project-board changes
+  (e.g. moving an issue between columns) through it; that has to be done
+  manually in the Gitea UI.
+
 ## Commit conventions
 
 - Commit messages: imperative mood subject line, no period, body explains