Let the coordinator manage skills, MCP servers and tools, behind a confirm card

- Coordinator tools in its own chat (super admin only): list_extensions,
  set_extension_access, delete_extension, and update_skill /
  update_mcp_server / update_custom_tool for what can't change where
  anything is sent (on/off, names, arguments, left-out tools)
- Adding a skill, MCP server or tool, or changing a skill's words, a
  server's URL or headers or a tool's kind or config, goes through
  propose_skill / propose_mcp_server / propose_custom_tool: stored in
  extension_proposals with the bot's background check, shown as a
  [proposal:ID] chip that opens a card with Confirm and Reject
- The card's facts are worked out by the app from what Confirm saves: the
  host, every {{env.KEY}} and whether it's saved, the config; for a skill
  its links, hosts, tool names, mentions of secrets and a diff against
  the saved runbook
- Confirming decides once and checks again; a server or tool missing a key
  is saved switched off, and the outcome is posted to the bot in chat
- Never from a bot: stdio servers, a URL whose host a template decides,
  envs in a prompt tool, a key's value

Co-Authored-By: Claude Opus 5.5 <[email protected]>

src/utils/link-computer-refs.test.ts

@@ -3,6 +3,7 @@ import botRef from "./bot-ref";
 import workspaceRef from "./workspace-ref";
 import computerRef from "./computer-ref";
 import linkComputerRefs from "./link-computer-refs";
+import proposalRef from "./proposal-ref";
 import takeOverRef from "./take-over-ref";
 
 describe("linkComputerRefs", () => {
@@ -20,6 +21,12 @@ describe("linkComputerRefs", () => {
         expect(linkComputerRefs({ text })).toBe(text);
     });
 
+    test("links proposals", () => {
+        expect(linkComputerRefs({ text: `Review it: ${proposalRef({ id: 7 })}` })).toBe(
+            "Review it: [proposal 7](#proposal-7)",
+        );
+    });
+
     test("links take-over requests", () => {
         expect(
             linkComputerRefs({