Move secrets between users and computers without the model seeing them

A new personal env scope (paradigm user: one user's secret for one bot)
beats every other scope, reaches only that user's runs of that bot, and
is redacted like any secret. Bots take secrets in with request_secret,
which puts a [secret-request:ID] card in the chat: the user types the
value into a masked input there, never into a message, and the bot is
told only the key. Bots show secrets with capture_secret (a task's
computer tool that saves a file or a command's output straight to a
personal env, then redacts it from the rest of the run) and show_secret
(an env by key): both give a [secret:ID] chip whose Reveal and Copy fetch
the value on click, for its own user (personal) or a super admin
(anything else), logged by key. Values never go into messages, page
props, history, Copy chat or logs. Users manage their own secrets on
Settings > Secrets; the Environment page lists everyone's, remove only.
Deleting a bot or user removes its personal secrets, and SecretsNote
tells bots never to ask for or print secrets in chat.

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

src/utils/export-message-text.test.ts

@@ -14,6 +14,12 @@ describe("exportMessageText", () => {
         ).toBe("@Ada and a bot in #Launch on computer 4, see file 12 and `seo/raw`. (take over computer 4, browser)");
     });
 
+    test("words secrets and secret requests by number, never a value", () => {
+        expect(exportMessageText({ text: "Here: [secret:12]. [secret-request:4]", ...names, heading_offset: 0 })).toBe(
+            "Here: (secret 12, hidden). (secret request 4)",
+        );
+    });
+
     test("leaves refs that are already links alone", () => {
         expect(exportMessageText({ text: "[bot:3](#x)", ...names, heading_offset: 0 })).toBe("[bot:3](#x)");
     });