fix: resolve pre-existing TypeScript errors to pass CI

- arrayfuncs.ts: rename inplaceColumnScale to inplaceDenseColumnScale (dedup)
- estimator_checks.ts: rename getConfig/setConfig to getChecksConfig/setChecksConfig (dedup)
- estimator_html.ts: getParams → get_params to match BaseEstimator API
- deprecation.ts: unknown → object return type for class decorator
- linalg.ts: fix compound assignments on possibly-undefined indexed values
- utils_ext10.ts: fix counts[bin]++ and Math.erf usage; import normalCDF
- utils_ext3.ts: fix counts[...].++ with noUncheckedIndexedAccess pattern
- utils_ext8.ts: fix xh[i] += eps compound assignment
- utils_ext9.ts: fix Float64Array.flat() flattening with manual loop
- weight_vector.ts: fix compound assignment on indexed Float64Array
- tree_utils.ts: fix counts[ci]++ and importances[feature] += patterns

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

Author: github-actions[bot]

src/utils/deprecation.ts

@@ -109,11 +109,7 @@ export function deprecated<T extends (...args: unknown[]) => unknown>(
  * whenever the class is instantiated.
  */
 export function deprecatedClass(options: DeprecationOptions = {}) {
-  // biome-ignore lint/suspicious/noExplicitAny: mixin class requires any[] per TypeScript spec
-  return <T extends new (...args: any[]) => object>(
-    Base: T,
-    ctx?: { name?: string },
-  ): T => {
+  return <T extends new (...args: unknown[]) => object>(Base: T, ctx?: { name?: string }): T => {
     const name = ctx?.name ?? Base.name;
     return class extends Base {
       constructor(...args: any[]) {