fix(schema | api-ref): improve variable declaration extraction, internal type-ref resolution, module indexing, and includeFiles glob support

[luvkapur]

This PR improves schema extraction accuracy, module indexing, and internal module resolution across several core parts of the API reference pipeline.

1. VariableDeclaration and ObjectLiteral handling

Fixes incorrect schema extraction for VariableDeclaration nodes initialized with object literals that contain identifier references.

Previously:

• Such cases often produced UnImplementedSchema or inlined FunctionLikeSchema nodes due to QuickInfo-based heuristics misclassifying object literals as arrow functions.

Now:

• VariableDeclarationTransformer explicitly detects ObjectLiteralExpression initializers and calls computeSchema() to construct accurate nested schemas.
• ObjectLiteralExpressionTransformer resolves previously unhandled UnImplementedSchema values by inspecting property initializers:
• Identifier initializers → resolved via getTypeRef() / getTypeRefForExternalNode() to produce proper TypeRefSchemas.
• Non-identifier initializers → fallback to resolveType() using parsed QuickInfo.
• SchemaExtractorContext now prioritizes object-literal detection in unknownExactType() before function heuristics, preventing false positives for FunctionLikeSchema.
• Hardened regex for createFunctionSchema() (^\s*([^)]+)\s*(?:=>|:)\s*(.+)$) to prevent over-matching and ensure stable parsing of function signatures.

2. Internal module extraction overhaul + recursive type-ref closure

Major overhaul of how internal (non-exported) modules are discovered, walked, and materialized.

Key changes:

• Introduces context.buildTopLevelNameIndex() to efficiently map names → top-level declarations.

• Internal modules now derive solely from identifiers not exported via the main entry point.

• Avoids any reprocessing of exported symbols handled by ExportDeclarationTransformer.

• Adds recursive closure over internal type references inside the same file:

  • collectSameFileInternalTypeRefs() walks the generated schema graph and finds all internal TypeRefSchema nodes belonging to the same file.
  • computeInternalModules() now performs a BFS:
    • root internal names (non-exported)
    • ALL internal names they reference transitively

Result: internal types are now fully resolved, transitive, and correctly represented.

3. includeFiles support for explicit internal parsing

Adds the ability for consumers to explicitly include additional files for full schema extraction

Behavior:

• includeFiles paths (or globs) are fully parsed and merged into internals of the APISchema.