feat(cli): codegraph version command + complete CLI Reference (#864)

* feat(cli): codegraph version command + complete CLI Reference

Add a `codegraph version` subcommand plus the `-v` and `-version`
spellings (commander already wires up `--version`/`-V`), so the version
is easy to reach however a user guesses at it. The `-v`/`-version` forms
are intercepted before commander parses — its version short flag is the
capital `-V`, and its parser rejects a multi-character single-dash flag.
A trailing `-v` on a subcommand still means `--verbose`.

Document the previously-missing commands in the README CLI Reference:
`daemon`/`daemons`, `unlock`, `telemetry`, `version`, and `help`.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

* docs(changelog): reference #864 on the version-command entry

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

---------

Co-authored-by: Claude Opus 4.8 <noreply@anthropic.com>

CHANGELOG.md

@@ -12,6 +12,7 @@ and adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.html).
 ### New Features
 
 - New `codegraph daemon` command (alias `daemons`) — an interactive manager for the background daemons. It shows what's running (your current project's daemon first, pre-selected), and you arrow-key to one and press enter to stop it, or pick "Stop all". Previously the only way to shut a daemon down was to hunt for its pid and `kill` it by hand. (#845)
+- Checking your installed version is now easy to reach however you guess at it: `codegraph version`, `codegraph -v`, and `codegraph -version` all print it, alongside the existing `codegraph --version`. (#864)
 - The CodeGraph MCP server now self-heals if its main thread ever locks up. A lightweight watchdog notices when the process has stopped responding and stops it so a fresh one starts on your next request — it can no longer sit pinned at 100% CPU with no way to recover. Tune the detection window with `CODEGRAPH_WATCHDOG_TIMEOUT_MS`, or turn it off entirely with `CODEGRAPH_NO_WATCHDOG=1`. (#850)
 
 ### Fixes