dsh-codex-composer: Bringing Codex-style input feel to DSH Web GUI

A DSH client plugin maintained by sakura-hly that adds a Codex-style keyboard feel to the Web GUI input box: ↑/↓ recalls previous prompts; Tab performs history completion when the draft contains text, and generates the next suggestion via the current session's model routing when the draft is empty (does not spawn agents, but is billed by provider). History is stored in localStorage, isolated by Session, with a maximum of 100 entries; it supports automatic seeding from the event stream and persistence after restarts. It targets compatibility with DSH >= 0.2.1-rc.3 (Web profile), relying solely on local routing and existing host services without modifying app.asar. To install, use `dsh plugin --profile desktop add <local-path>`, or manually add the bundle, run `pnpm install`, and restart. To completely remove the takeover, disable it in Settings → Plugins. The repository has 0 stars and is under the MIT license; it is an early-stage project, so please read the source code before installing. Note that context suggestions will consume actual tokens during use.