fix(checker): check type expressions on unmatched JSDoc @param tags

[Zelys-DFKH]

Fixes #3742

Hat tip to @hkleungai: the side-by-side tsc/tsgo output in that thread made the gap easy to trace.

checkUnmatchedJSDocParameters correctly emits TS8024 when a @param name doesn't match any real parameter, but it drops the type expression without checking it. So @param {Record} bar on a zero-parameter function gives you TS8024 and silently misses TS2314 ("Generic type 'Record' requires 2 type argument(s)"). tsc reports both.

Analysis

For matched params, the type expression reaches checkSourceElement through checkVariableLikeDeclaration, which is what triggers checkTypeReferenceNode and eventually TS2314 for things like Record. For unmatched params, the loop calls errorOrSuggestion for TS8024 and then moves on. The type expression is never touched.

Fix

After the TS8024 emission (or the isNameFirst skip), check the tag's type expression if present. Two guards are needed:

JS files only. In .ts files, JSDoc types are documentation, not the type system. Without the isJs gate, a local variable name used as a @param type (common in tsc's own checker.ts) incorrectly surfaces TS2304 ("Cannot find name 'X'"). Every other JSDoc type check in the checker observes the same boundary.

Skip signature types. KindFunctionType, KindConstructorType, KindCallSignature, KindConstructSignature, and KindIndexSignature all dispatch to checkSignatureDeclaration, which calls checkParameter on the signature's parameter list. Those parameters are not symbol-bound inside JSDoc type expressions, so getSymbolOfDeclaration returns nil, causing a nil-pointer panic. Callback-style @param {(x: T) => U} fn types are excluded from checking for now; recovering diagnostics from inside those signatures is a separate, harder problem.

Test

Added testdata/tests/cases/compiler/jsdocUnmatchedParamTypeChecked.ts: a JS file with @param {Record} bar on a zero-parameter function. The baseline shows both TS2314 and TS8024, matching tsc output.

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[RyanCavanaugh]

Closing automated PRs; please don't run automated coding tools against this repo. We're fully able to do that ourselves.