feat: v2.7.6 — edit users in one form, Settings → Account, display names, copy over plain HTTP

- Users page: one Edit user form (display name, email, role, active, a new or
  generated password, workspaces given or taken back, sign out everywhere),
  validated as a whole before anything is written (PATCH /api/users/:id,
  GET /api/users/:id); users.display_name/email added migration-safe.
- Settings → Account for every signed-in user: profile, own password (the
  current one required, this login kept), sign out other devices
  (/api/me/account, /api/me/password, /api/me/sign-out-others; login cookie
  only, never a pane token).
- Display names wherever a person is named (sidebar, workspace owner groups,
  Users page and audit log); owner_display_name / reader_display additive.
- Users page: admins add and remove Claude/Codex pool accounts.
- Folder browser: an admin with their own Linux account opens in their home;
  the "Server folder" tick opens the host's (never remembered).
- AI Proxy: "Config 9router" beside Add profile when 9router is installed,
  opened on the dashboard's own host (GET /api/ai-proxies/9router).
- Terminal: a tmux selection reaches the clipboard over plain HTTP too
  (writeClipboard's textarea fallback, focus handed back).
- Chat: a file the session touched outside the workspace previews
  (GET /api/sessions/:id/file).
- install-system: `!requiretty` only when visudo accepts it (sudo-rs on
  Ubuntu 25.10+ rejects the setting).
- openapi.yaml regenerated; docs (API, SERVER-MODE, LANES) updated.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

server/routes/sessions.js

@@ -543,6 +543,71 @@ router.get("/:id/image", async (req, res) => {
   }
 });
 
+// A text file the session's own Read, Write, Edit, MultiEdit or NotebookEdit
+// named (`?path=`, exact), for the Chat pane's Outputs/Files preview when it
+// lies outside the workspace (a report written to ~/Documents, issue #76).
+// The same authorization as `/image` — that event, never a pushed session,
+// server mode only with S3 and a member's session only inside their own home
+// on a file they own — plus: never a credential by name
+// (`isSecretConfigPath`, a `settings.local.json`), never a binary or a
+// non-regular file, at most READ_TEXT_MAX bytes (the rest is `truncated`).
+const READ_TEXT_MAX = 512 * 1024;
+const sessionTouchedFile = db.prepare(
+  `SELECT 1 FROM events
+   WHERE session_id = ? AND event_type = 'PostToolUse'
+     AND tool_name IN ('Read', 'Write', 'Edit', 'MultiEdit', 'NotebookEdit')
+     AND (json_extract(data, '$.tool_input.file_path') = ?
+       OR json_extract(data, '$.tool_input.notebook_path') = ?)
+   LIMIT 1`
+);
+router.get("/:id/file", async (req, res) => {
+  const fail = (status, code, message) => res.status(status).json({ error: { code, message } });
+  const session = stmts.getSession.get(req.params.id);
+  if (!session) return fail(404, "NOT_FOUND", "Session not found");
+  const s3 = require("../lib/linux-accounts").s3Enabled();
+  if ((isServerMode() && !s3) || String(session.source || "").startsWith("push:")) {
+    return fail(403, "EUNSUPPORTED", "not available for this session");
+  }
+  const file = typeof req.query.path === "string" ? req.query.path : "";
+  if (!path.isAbsolute(file)) return fail(400, "EBADPATH", "not an absolute path");
+  const { isSecretConfigPath } = require("../lib/cc-discovery");
+  const secret = (p) =>
+    isSecretConfigPath(p) || path.basename(p).toLowerCase() === "settings.local.json";
+  if (secret(file)) return fail(403, "ESECRET", "a credential file is never served");
+  const runAs = require("../lib/run-as");
+  const member = s3 ? runAs.ownerForRead(session.cwd) : null;
+  if (member && !require("../lib/hook-auth").inside(member.home, file)) {
+    return fail(404, "ENOTFOUND", "the session never touched that file");
+  }
+  if (!sessionTouchedFile.get(session.id, file, file)) {
+    return fail(404, "ENOTFOUND", "the session never touched that file");
+  }
+  let fh;
+  try {
+    // By what it RESOLVES to as well: a link named `notes.md` to a key file.
+    if (secret(await fs.promises.realpath(file))) {
+      return fail(403, "ESECRET", "a credential file is never served");
+    }
+    // NONBLOCK: a FIFO must not hang the event loop.
+    fh = await fs.promises.open(file, fs.constants.O_RDONLY | (fs.constants.O_NONBLOCK || 0));
+    const st = await fh.stat();
+    const fileOwner = s3 ? runAs.ownerForRead(file) : null;
+    if (!st.isFile() || (fileOwner && st.uid !== fileOwner.uid)) {
+      return fail(404, "ENOTFOUND", "no such file");
+    }
+    const buf = Buffer.alloc(Math.min(st.size, READ_TEXT_MAX));
+    const { bytesRead } = await fh.read(buf, 0, buf.length, 0);
+    const head = buf.subarray(0, bytesRead);
+    if (head.subarray(0, 8000).includes(0)) return fail(415, "EBINARY", "not a text file");
+    res.set("Cache-Control", "no-store");
+    res.json({ text: head.toString("utf8"), truncated: st.size > READ_TEXT_MAX });
+  } catch {
+    if (!res.headersSent) fail(404, "ENOTFOUND", "no such file");
+  } finally {
+    await fh?.close();
+  }
+});
+
 /** The `/:id/stats` body — also frozen into a session snapshot. */
 function sessionStats(sessionId) {
   const totalEvents = stmts.sessionEventCount.get(sessionId)?.count ?? 0;