fix(extraction): classify TS/JS class fields by value — properties, not methods (#808) (#809)

Every TS `public_field_definition` / JS `field_definition` extracted as a
method-kind node, so a plain field (`public fonts: Fonts;`) was reported
as callable: class shape was misrepresented, kind-based filtering was
defeated, and bare-name call resolution landed on data fields — typeorm's
boolean `ColumnMetadata::isArray` field was soaking up Array.isArray(...)
call edges (685 such wrong edges on typeorm alone).

Classification now follows the VALUE (classifyMethodNode hook, mirroring
resolveBody's callable detection): arrow-function / function-expression
fields and HOF-wrapped ones (`onScroll = throttle(() => {…})`) stay
methods with their bodies walked; everything else becomes a property that
keeps its type-annotation references edge, visibility, static-ness, and
decorators. Field initializers are now walked too (`history =
createHistory()` attributes the call to the property — previously
invisible), and JS class fields — whose name lives in the grammar's
`property` field, so they never extracted a symbol at all — now appear in
the graph (resolveName on the JS extractor).

With fields correctly kinded, `this.X` callback registration is re-enabled
for TS/JS (removed in #807 because field pseudo-methods made it mostly
wrong): `this.<member>` candidates resolve CLASS-SCOPED
(resolveThisMemberFnRef) — the target must be a function/method sharing
the from-symbol's qualified-name class prefix, same file, no fallback —
so `addEventListener("online", this.onOfflineStatusToggle)` and API-object
wiring (`{ mutateElement: this.mutateElement }`) produce registration
edges to the enclosing class's own method, while `this.fonts` (a
property) and inherited/unknown members yield no edge.

A/B (baseline = #807 main): excalidraw / typeorm / express — node counts
identical on all three; kinds shift method→property only (typeorm: exactly
7,406 swapped; excalidraw also corrects 5 anonymous-class mock fields that
were function-kind); every one of the 736 dropped call edges targeted a
node that is now a property (calls into data fields — verified 100%);
gains are retargets to real callables, initializer-call attributions, and
+74/+7 class-scoped this.X registration edges (sampled: addEventListener/
removeEventListener wiring, imperative-API method maps). Full suite green
(1386).

EXTRACTION_VERSION 19 → 20 (re-index to benefit).

Closes #808

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

src/extraction/tree-sitter-types.ts

@@ -180,6 +180,15 @@ export interface LanguageExtractor {
    */
   classifyClassNode?: (node: SyntaxNode) => 'class' | 'struct' | 'enum' | 'interface' | 'trait';
 
+  /**
+   * Classify a methodTypes node when the grammar reuses one node type for
+   * both callable and data members (#808): TS/JS class FIELDS
+   * (`public_field_definition` / `field_definition`) are methods only when
+   * their value is callable (`onClick = () => {}`); a plain field
+   * (`public fonts: Fonts;`, `count = 0`) is a property. Default: 'method'.
+   */
+  classifyMethodNode?: (node: SyntaxNode) => 'method' | 'property';
+
   /**
    * Resolve the body node for a function/method/class when it's not a child field.
    * (e.g. Dart puts function_body as a sibling, not a child.)