TSExternalSymbol has multiple versions

[georgesafta]

Describe the bug
TSExternalSymbol model out of sync

It's defined as:

class TSExternalSymbol(_Base):
    """A WALA-style phantom node: a synthetic stub for a call target OUTSIDE the project (an
    imported/required library member). An edge's ``target`` byte-matches either a real
    ``TSCallable.signature`` or a ``TSExternalSymbol.signature``, so the call graph stays
    dangling-free while still recording external (e.g. sink) calls.

    Slim: the map key in ``TSApplication.external_symbols`` IS the signature (e.g.
    ``commander.parse``), and membership already means external — so neither is repeated here."""

    name: str
    module: str

while from Neo4J it is constructed as:

def external(props: Props) -> TSExternalSymbol:
    return TSExternalSymbol(
        signature=props.get("signature", ""),
        name=props.get("name", ""),
        module=props.get("module", ""),
        kind=props.get("kind", "unknown"),
    )

A similar behavior is present in the codeanalyzer:

• https://github.com/codellm-devkit/codeanalyzer-typescript/blob/main/src/schema/schema.ts#L377C1-L380C2
• neo4j schema: https://github.com/codellm-devkit/codeanalyzer-typescript/blob/main/src/build/neo4j/schema.ts#L191

To Reproduce
Load TS model from an application with external symbols.

Expected behavior
Single model

Logs
No

Additional context
No