fix(cli): make node symbol positional optional so node -f <file> works (#1044) (#1051)

`codegraph node` was defined with a required `<name>` positional, so
commander.js rejected `codegraph node -f <file>` with "missing required
argument 'name'" before the action ran — making file-read mode (the CLI
face of the codegraph_node MCP tool's file mode) unreachable. The action
body already handled an absent name.

Make `name` optional (`[name]`), validate that a symbol or a file is
supplied (friendly usage hint instead of a cryptic commander error when
neither is), and guard the name-based arg branches so they never run on
undefined. Adds an end-to-end regression test across all four paths.

Co-authored-by: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

CHANGELOG.md

@@ -17,6 +17,7 @@ and adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.html).
 - C++ classes that inherit from a templated base — `class Widget : public Base<int>`, a CRTP base like `class App : public CRTPBase<App>`, or a struct inheriting a template — are now linked to that base class in the graph. Previously the template arguments (`<int>`) made the inheritance go unrecognized, so these classes looked like they inherited from nothing and impact/callers analysis stopped at the boundary; the connection is now followed like any other base class. Thanks @ryancu7 for the report. (#1043)
 - C++ objects constructed on the stack — `Calculator calc(0)` or `Widget w{1, 2}` — now record that the enclosing function instantiates that class, the same as heap construction (`new Calculator(0)`) already did. Previously only the `new` form was tracked, so a function that built objects with the ordinary stack syntax looked like it didn't construct them and the dependency was missing from impact/callers. Thanks @Dshuishui for the report. (#1035)
 - The graph no longer stores duplicate copies of the same relationship. The same dependency between the same two symbols at the same spot could be recorded more than once, which inflated edge counts and let callers/impact results list a relationship twice. Each relationship is now stored exactly once, and existing projects are de-duplicated automatically the next time CodeGraph opens them. Thanks @inth3shadows for the detailed report. (#1034)
+- `codegraph node` can now read a file from the command line. File-read mode — pass `-f`/`--file` to get a file's source with line numbers plus the files that depend on it, the same output as the `codegraph_node` MCP tool — was rejected with "missing required argument 'name'", because the command always demanded a symbol name even though file mode has none, leaving the feature unreachable from the CLI. The symbol name is now optional: `codegraph node -f src/auth.ts` (or `codegraph node src/auth.ts`) reads the file, `codegraph node parseToken` looks up a symbol, and running it with neither prints a short usage hint instead of a cryptic error. Thanks @jcrabapple for the report. (#1044)
 
 
 ## [1.1.2] - 2026-06-28