fix(#592): clamp the COPILOT_* variables that bypass approval, run code or move the token

The COPILOT_ prefix admits every variable Copilot reads, and the 1.0.98
bundle reads far more than `copilot help environment` lists. Only
COPILOT_HOME, COPILOT_ALLOW_ALL and the BYOK trio were privileged, so a
non-granted multi-user owner could still hand back what the allowAll
clamp removed:

- approval: COPILOT_PLAN_THEN_AUTOPILOT, COPILOT_ASSISTED_APPROVAL
- code with no approval row: COPILOT_CLI_DIST_DIR runs <dir>/index.js
  in place of the CLI, the package caches choose the CLI build,
  COPILOT_EDITOR, COPILOT_PROVIDER_API_KEY_COMMAND and
  COPILOT_AHP_HOST_BIN are executed, skills, provider configs and hooks
  are loaded from the named places (the DSH_HOME class)
- token redirects: COPILOT_API_URL and the other API bases receive the
  CLI's sign-in token, which in multi-user mode is the operator's (all
  users share the OS account and ~/.copilot), and the rest of the BYOK
  provider family re-aims a Codeman custom endpoint (the
  DEEPSEEK_BASE_URL / OMP_AUTH_BROKER_URL class)

All are now privilegedEnvKeys. The registry schema capped that list at 8;
the cap is now 48, since a longer deny list only takes more away from
non-granted owners. The test sends one of each class through the real
schema (they all pass it) and the real clamp. The docs say the list is
read from the 1.0.98 bundle and that a variable a later release adds is
not covered until it is listed.

Co-Authored-By: Claude Opus 5.5 (1M context) <noreply@anthropic.com>

docs/cli-registry.md

@@ -352,4 +352,4 @@ The rules the module keeps and the tests pin: it only ADDS (a name already defin
 
 `copilot` (npm `@github/copilot`) is a stock entry. A bare launch is `copilot`, in its own Manual Approval mode. The launch parameters follow the grok/omp shape: `model` (`--model`), `resumeId` (`--resume <id>`, an id, id prefix or session name: a single word that starts with a letter or digit, so a flag-shaped value such as `--yolo` is dropped rather than read as its own flag) and `continueSession` (`--continue`, skipped when a resume id is set), plus `allowAll` (`--yolo`: allow every tool, path and URL). The legacy config object is `copilotConfig` (`{ model, allowAll, resumeSessionId, continueSession }`). The Run button sends `allowAll: true` like the other agent CLIs' bypass switches, and `allowAll` is declared in `privilegedParams`, so a non-granted multi-user owner has it forced back to `false` (an absent config is never materialized: a bare spawn is already safe). Session history resume goes through `copilotConfig.resumeSessionId` / `continueSession`. The tab names the model it reads from the footer (`modelDetect`). Its `altScreen` is `strip-mux-and-mouse`, like opencode: Copilot turns mouse tracking on itself, and left in, a plain drag is reported to the TUI instead of selecting (Auto Copy and copy-on-select did nothing); stripped, a drag is a local selection, clicks go through the hand-encoded tap, and the wheel is forwarded as SGR reports while `cliMouseTracking` is on. It declares `mcpConfig` (`~/.copilot/mcp-config.json`, relocated by `COPILOT_HOME`) and no `credStore`: its token sits in `config.json` in plain text on a host without a keyring, so a Docker case is not seeded and you sign in inside the container. `env.allowedKeys` is empty on purpose: a headless host sets `COPILOT_GITHUB_TOKEN`, which the `COPILOT_` prefix admits, and `GH_TOKEN`/`GITHUB_TOKEN` stay out of the one global allowlist.
 
-Measured on 1.0.94 inside tmux: an alternate-screen TUI with mouse tracking on, whose composer is the `❯` between two rules. While a turn runs the footer reads `◉ Working esc edit prompt` (the dot alternates `◉`/`◎`), which is the `workDetect` working line. Keystrokes sent with `tmux send-keys` reach the composer, Shift+Enter inserts a newline, and a shell tool call completes inside tmux; github/copilot-cli#4180 (a driven PTY ignores input) and #4223 (a shell command never completes under tmux) report both failing on 1.0.70 to 1.0.74 and neither reproduces on 1.0.94. `COPILOT_HOME` and `COPILOT_ALLOW_ALL` are privileged env keys, so a non-granted multi-user owner cannot set them through `envOverrides`.
+Measured on 1.0.94 inside tmux: an alternate-screen TUI with mouse tracking on, whose composer is the `❯` between two rules. While a turn runs the footer reads `◉ Working esc edit prompt` (the dot alternates `◉`/`◎`), which is the `workDetect` working line. Keystrokes sent with `tmux send-keys` reach the composer, Shift+Enter inserts a newline, and a shell tool call completes inside tmux; github/copilot-cli#4180 (a driven PTY ignores input) and #4223 (a shell command never completes under tmux) report both failing on 1.0.70 to 1.0.74 and neither reproduces on 1.0.94. `COPILOT_HOME` and `COPILOT_ALLOW_ALL` are privileged env keys, so a non-granted multi-user owner cannot set them through `envOverrides`, and so are the other `COPILOT_*` variables (read from the 1.0.98 bundle, far more than `copilot help environment` lists) that switch approvals, run code with no approval row or send the sign-in token elsewhere. The `COPILOT_` prefix admits whatever a later release adds, so the list needs a look whenever the measured version moves.