fix(resolution): a definition its language makes file-local is not a cross-file target (#1731) (#1745)

* fix(resolution): a definition its language makes file-local is not a cross-file target

Name matching accepted any same-named definition as the target of a call
from another file, however the language scopes it. isVisibleAcrossFiles
now declines, for a candidate in another file:

  C / C++   a function whose definition line carries `static` (read from
            source — the extractor records no storage class, and the kernel
            arm would need the same field)
  Kotlin, Java, C#, Swift, Scala, Dart, PHP
            visibility === 'private'
  Go        a lowercase identifier from another directory (by the name's
            case: the extractor's isExported is unset for every Go method)
  Rust      a non-`pub` item unless the reference is in the item's module
            subtree (a child sees its ancestors' private items via super::);
            a method in an `impl Trait for Type` block has the trait's
            visibility and is exempt

The test runs in ReferenceResolver on the target the whole name-matching
pipeline settled on, so a rejection ends the reference unresolved. Declining
inside matchByExactName instead let the ref fall through to matchFuzzy,
which committed to a same-language namesake the ranking had passed over —
eight edges on one tree, all onto a local `const fail = …` arrow the graph
does not hold. matchFuzzy checks its own survivor too; nothing runs after it.

Five corpora, all against b9ca4b7, wasm arm, edge rows keyed with
resolvedBy:

  betaflight fork (2,109 C files)        LOST 4,451  GAINED 0   (#1730)
  Android/Go/JS app (114 kt, 42 go)      LOST   142  GAINED 0   (#1731)
  emmc-reader-gui (71 rs)                LOST   195  GAINED 0
  skylab_hub (35 rs)                     LOST    92  GAINED 0
  vitejs/vite (JS/TS only)               LOST     0  GAINED 0

Samples read back: `Vec::new()` onto a private `fn new` in another crate,
`ui.add(…)` (egui) onto a private `add`, `latch.await()` onto a test file's
`private fun await`, `leaflet.js` onto an unexported Go `func add`,
`usbd_get_descriptor` onto a `static get_device_descriptor` in a USB class
file it never links.

Fixes #1730. Fixes #1731.

Co-Authored-By: Claude Fable 5.1 <noreply@anthropic.com>

* fix(resolution): a static in a header is part of every unit that includes it

The C rule declined any `static` function defined in another file. A
`static` in a SOURCE file is local to that translation unit and the rule is
right there; a `static` in a header — `static inline`, the whole of
MAVLink's generated `mavlink_msg_*.h` — is textually included into every
unit that names it, and the call is real. On the betaflight tree 4,306 of
the 4,451 rows the first cut removed were exactly that: `testsuite.h` and
`mavlink_msg_*.h` calling `protocol.h`'s `_mav_put_char_array`,
`mav_array_assign_char` and each other's `_pack` / `_decode` helpers.

The rule now applies only to a candidate whose file is a translation unit
(`.c .cc .cpp .cxx .c++ .m .mm`). Same tree: LOST 145, GAINED 0, every one
onto a `static` in another `.c` — STM32 USB class sources onto GD32's
`usbd_enum.c`, and the USB descriptor table shape from #1730. Header
targets in the removed set: 0.

Co-Authored-By: Claude Fable 5.1 <noreply@anthropic.com>

* docs(changelog): cite #1731 and narrow the C file-local note

Rebased #1732 onto latest main. Clarify that only a static in another
source file is declined (header static inline stays), name the Kotlin/Go/Rust
shapes from #1731, and note the post-pipeline placement that avoids fuzzy
fallback.

---------

Co-authored-by: danusha2345 <ewidusoc498@gmail.com>
Co-authored-by: Claude Fable 5.1 <noreply@anthropic.com>
Co-authored-by: Colby McHenry <colbymchenry@users.noreply.github.com>

src/resolution/index.ts

@@ -16,7 +16,7 @@ import {
   FrameworkResolver,
   ImportMapping,
 } from './types';
-import { matchReference, matchFunctionRef, matchDottedCallChain, matchScopedCallChain, matchMethodCall, sameLanguageFamily, crossesKnownFamily, dumpNameMatcherProfile, clearNameMatcherMemos } from './name-matcher';
+import { isVisibleAcrossFiles, matchReference, matchFunctionRef, matchDottedCallChain, matchScopedCallChain, matchMethodCall, sameLanguageFamily, crossesKnownFamily, dumpNameMatcherProfile, clearNameMatcherMemos } from './name-matcher';
 import { resolveViaImport, resolveJvmImport, extractImportMappings, extractReExports, loadCppIncludeDirs, isPhpIncludePathRef, isCobolCopybookRef, isNixPathImportRef, clearImportResolverMemos } from './import-resolver';
 import { ResolverPool, minRefsForPool } from './resolver-pool';
 import { detectFrameworks } from './frameworks';
@@ -1012,7 +1012,13 @@ export class ReferenceResolver {
     // binding it happened to pick. Same-file matches only.
     if (nameResult) {
       const target = this.queries.getNodeById(nameResult.targetNodeId);
-      if (ref.language === 'nix') {
+      // A definition its language makes file-local — a C `static`, a Kotlin
+      // `private fun`, a Go unexported name in another package, a Rust
+      // non-`pub` item outside its module subtree — cannot be what a name in
+      // another file means, whichever strategy chose it (#1730).
+      if (target && !isVisibleAcrossFiles(target, ref, this.context)) {
+        nameResult = null;
+      } else if (ref.language === 'nix') {
         if (!target || target.filePath !== ref.filePath) {
           nameResult = null;
         }