[codex] harden authenticated routes and issue editor reliability (#3741)

## Thinking Path

> - Paperclip orchestrates AI agents for zero-human companies
> - The control plane depends on authenticated routes enforcing company
boundaries and role permissions correctly
> - This branch also touches the issue detail and markdown editing flows
operators use while handling advisory and triage work
> - Partial issue cache seeds and fragile rich-editor parsing could
leave important issue content missing or blank at the moment an operator
needed it
> - Blocked issues becoming actionable again should wake their assignee
automatically instead of silently staying idle
> - This pull request rebases the advisory follow-up branch onto current
`master`, hardens authenticated route authorization, and carries the
issue-detail/editor reliability fixes forward with regression tests
> - The benefit is tighter authz on sensitive routes plus more reliable
issue/advisory editing and wakeup behavior on top of the latest base

## What Changed

- Hardened authenticated route authorization across agent, activity,
approval, access, project, plugin, health, execution-workspace,
portability, and related server paths, with new cross-tenant and
runtime-authz regression coverage.
- Switched issue detail queries from `initialData` to placeholder-based
hydration so list/quicklook seeds still refetch full issue bodies.
- Normalized advisory-style HTML images before mounting the markdown
editor and strengthened fallback behavior when the rich editor silently
fails or rejects the content.
- Woke assigned agents when blocked issues move back to `todo`, with
route coverage for reopen and unblock transitions.
- Rebasing note: this branch now sits cleanly on top of the latest
`master` tip used for the PR base.

## Verification

- `pnpm exec vitest run ui/src/lib/issueDetailQuery.test.tsx
ui/src/components/MarkdownEditor.test.tsx
server/src/__tests__/issue-comment-reopen-routes.test.ts
server/src/__tests__/activity-routes.test.ts
server/src/__tests__/agent-cross-tenant-authz-routes.test.ts`
- Confirmed `pnpm-lock.yaml` is not part of the PR diff.
- Rebased the branch onto current `public-gh/master` before publishing.

## Risks

- Broad authz tightening may expose existing flows that were relying on
permissive board or agent access and now need explicit grants.
- Markdown editor fallback changes could affect focus or rendering in
edge-case content that mixes HTML-like advisory markup with normal
markdown.
- This verification was intentionally scoped to touched regressions and
did not run the full repository suite.

## Model Used

- OpenAI Codex, GPT-5-based coding agent in the Codex CLI environment
with tool use for terminal, git, and GitHub operations. The exact
runtime model identifier is not exposed inside this session.

## Checklist

- [x] I have included a thinking path that traces from project context
to this change
- [x] I have specified the model used (with version and capability
details)
- [x] I have run tests locally and they pass
- [x] I have added or updated tests where applicable
- [x] If this change affects the UI, it is behavior-only and does not
need before/after screenshots
- [x] I have updated relevant documentation to reflect my changes, or no
documentation changes were needed for these internal fixes
- [x] I have considered and documented any risks above
- [x] I will address all Greptile and reviewer comments before
requesting merge

---------

Co-authored-by: Paperclip <noreply@paperclip.ing>

server/src/app.ts

@@ -86,6 +86,16 @@ function shouldServeViteDevHtml(req: ExpressRequest): boolean {
   return req.accepts(["html"]) === "html";
 }
 
+export function shouldEnablePrivateHostnameGuard(opts: {
+  deploymentMode: DeploymentMode;
+  deploymentExposure: DeploymentExposure;
+}): boolean {
+  return (
+    opts.deploymentExposure === "private" &&
+    (opts.deploymentMode === "local_trusted" || opts.deploymentMode === "authenticated")
+  );
+}
+
 export async function createApp(
   db: Db,
   opts: {
@@ -123,8 +133,10 @@ export async function createApp(
     },
   }));
   app.use(httpLogger);
-  const privateHostnameGateEnabled =
-    opts.deploymentMode === "authenticated" && opts.deploymentExposure === "private";
+  const privateHostnameGateEnabled = shouldEnablePrivateHostnameGuard({
+    deploymentMode: opts.deploymentMode,
+    deploymentExposure: opts.deploymentExposure,
+  });
   const privateHostnameAllowSet = resolvePrivateHostnameAllowSet({
     allowedHostnames: opts.allowedHostnames,
     bindHost: opts.bindHost,