fix(cpp): a call through a class the index doesn't hold gets no guess by a shared word

CHANGELOG.md

@@ -256,6 +256,7 @@ and adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.html).
 - In TypeScript and JavaScript, an import of a package your project declares itself with `declare module '…'` in a `.d.ts` file, like a `typings/mammoth/index.d.ts` written for an untyped package or VS Code's own `vscode.d.ts`, now links to that declaration, so `codegraph callers`, impact and `codegraph affected` show the code that uses your typings instead of nothing or a project symbol that only shares a name. Named, default and namespace imports, `export =` and renaming export lists are read the way TypeScript reads them, a function such a file declares without a body (`export function convertToHtml(…): Promise<Result>;`) is now indexed so calls to it have something to link to, and only an import of its package reaches it. A `declare module` that augments a package's own types, a wildcard like `declare module '*.svg'`, and copies of typings kept in test fixtures are left alone. Re-index TypeScript projects after upgrading.
 - In TypeScript, an interface that extends other interfaces, like `interface UserRepo extends Repo<User>, Named`, is now linked to each of them: the type hierarchy shows them above the interface and above every class that implements it, a change to an interface reaches the interfaces built on it and their implementations in impact results, and a call on a value typed by such an interface, like `hass.formatEntityName(…)` on a `HomeAssistant` that extends seven interfaces, links to the method the interface inherits instead of a same-named method elsewhere. Before, only a class's `extends` and `implements` were read, so every interface stood alone. A type from a package, like `ButtonProps` from `@mui/material`, or one of TypeScript's own, like `Omit<…>`, still links to nothing rather than to a type of the same name elsewhere in your project. Re-index TypeScript projects after upgrading.
 - In TypeScript and JavaScript, a type, class, constant or other declaration that a `.d.ts` file declares inside `declare module '…'` now links only from files that use that module: files that import it, the module's other declarations, and files that import it through a file of yours that re-exports it. Before, any file using the same name linked to it: Node's `import { readFileSync } from 'fs'` linked to the `fs` that VS Code's `vscode.d.ts` declares, and a `ProcessEnv`, or an LSP `TextDocument` imported through a barrel, to the `vscode` module's types of those names. Re-index TypeScript projects after upgrading.
+- In C++, a call written through a class the index doesn't hold, like protocolbuffers/protobuf's `FeatureSet::descriptor()` or `OneofOptions::default_instance()` (both classes are declared in `descriptor.pb.h`, a file too large to index), no longer links to another class's method of that name whose class only shares a word with it, like `JavaFeatures_NestInFileClassFeature::descriptor` or `CppFileOptions::default_instance`. A class named like the call's would have been found first, so one that only shares a word is another class. A call through a template parameter, through an alias, including one the calling function or a macro it expands declares, or through a namespace the file opens, aliases or uses links as before, and so does a call of a method only one class in the project declares. Re-index C++ projects after upgrading.
 
 ## [1.6.2] - 2026-10-03