README: fix the Copilot pin install command and tighten the section

npm install -g @github/copilot@v1.0.84-5 does not resolve; no published
version carries a v prefix. The next line already used the bare version.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_016n4hSXVu6wLR4RCfnt6PPG

Author: scgopi

README.md

@@ -80,37 +80,24 @@ Releases are Developer ID signed and notarized.
 State lives in `~/.graphcode/` — graphs, recents, layouts, the daemon socket and logs, and the installed
 binaries. **Nothing is ever written inside a project folder you open.**
 
-### Use a known-good Copilot version
+### Pin a Copilot CLI version
 
-If a Copilot CLI update is broken, first install a known-good published version on each
-machine where Copilot runs, including remote hosts, and verify the reported version.
-For example:
+Copilot loops follow the CLI's own version selection. To hold a specific published version,
+install it on every machine that runs Copilot, including remote hosts:
 
 ```sh
-npm install -g @github/copilot@v1.0.84-5 &&
+npm install -g @github/copilot@1.0.84-5
 copilot --prefer-version 1.0.84-5 --version
 ```
 
-Only after installation succeeds and the reported version matches, set
-**Settings > Preferred versions > Copilot CLI** to **Specific version** and enter that version.
-The section follows **Permissions** and has one row per backend, all starting at **Default**.
-Claude Code, Codex, OpenCode, and Pi are locked to **Default** until version overrides are
-supported for them. This does not change which backend new loops or Quick Chats use.
-The Copilot field accepts any published version; `1.0.84-5` is just an example. GraphCode passes
-`--prefer-version <version>` to new and resumed Copilot sessions (app and daemon, local and
-SSH), and to Copilot title and summary requests. Running sessions are not interrupted.
-
-Settings provides a copyable install command for the chosen version; GraphCode does not run
-it automatically or verify installation before activating the preference. The preference
-takes effect immediately for subsequent launches. Keep `copilot` on the login shell's `PATH`.
-Without the app, set
-`"copilotPreferredVersion": "1.0.84-5"` in `~/.graphcode/settings.json` (or the workspace's
-`GRAPHCODE_SUPPORT_DIR/settings.json`), preserving the other keys. The setting is read on
-each launch, so no daemon restart is needed.
-
-Choose **Default**, clear the field, or remove the JSON key to stop passing `--prefer-version`.
-**Default** follows the CLI's own version selection; it does not install the latest release. If you also
-downgraded the global npm installation, run `npm install -g @github/copilot@latest` to update it.
+Then set **Settings ▸ Preferred versions ▸ Copilot CLI** to that version. GraphCode passes it to
+new and resumed Copilot sessions, locally and over SSH, and to Copilot title and summary
+requests; sessions already running are unaffected. Without the app, set
+`"copilotPreferredVersion": "1.0.84-5"` in `~/.graphcode/settings.json` — it is read on each
+launch, so no daemon restart is needed.
+
+Clear the field to return to the CLI's own selection. GraphCode installs nothing itself, so a
+version you have not installed on the host will not be there when a loop launches.
 
 ## Workspaces