Verify each finding against the current code and only fix it if needed.

Inline comments:
In `@crates/biome_js_analyze/src/lint/nursery/no_misleading_return_type.rs`:
- Around line 401-405: The bug is that build_inferred_description uses
annotation.flattened_union_variants() for union annotations instead of the
actual returned types; change the union branch to derive candidates from the
returns slice (e.g., collect flattened variants from each element of returns) so
the diagnostic reflects the inferred return types (modify the TypeData::Union(_)
arm to use returns.iter().flat_map(|r| r.flattened_union_variants()).collect()
or otherwise collect from returns, keeping the function
build_inferred_description, the returns parameter, and
annotation.flattened_union_variants() as reference points).
- Around line 108-111: The current early return suppresses diagnostics whenever
the annotated return type (effective_return_ty) includes undefined/void but none
of the collected explicit returns (returns from collect_block_returns) do;
instead, change the logic to look for bare returns and fall-through paths
explicitly: keep the diagnostic unless at least one collected return lacks an
expression (a bare `return`) or the function/block can fall through to an
implicit undefined (detectable by checking the block's final statement/exit
path), and only then suppress by returning None. Update the code that currently
references includes_undefined(&effective_return_ty) &&
!returns.iter().any(includes_undefined) to (1) inspect the collected returns for
any return node with no argument (bare return) and (2) check the block for a
possible fall-through/implicit return; if neither condition is true, do not
return None so the diagnostic is emitted.
- Around line 510-556: resolve_identifier_initializer_type and
identifier_refers_to_const_assertion currently match declarations by name across
the entire function body without regard to declaration order or lexical scope;
update both to perform scope- and order-aware binding resolution: start from the
usage node (id_expr / reference) and search for a matching binding only in
lexical scopes that enclose the usage (walk parent ancestors to find the nearest
enclosing block/function), and within each scope scan only preceding sibling
statements (and their nested declarations) — not later statements or
declarations inside nested inner blocks that do not lexically enclose the usage;
prefer using existing AST/symbol utilities if available, otherwise implement a
walker that checks ancestor scopes and prior siblings when looking for
JsVariableDeclarator/JsVariableStatement with the same identifier and a prior
source position before returning the initializer type in
resolve_identifier_initializer_type (and mirror the same ordering/scope rules in
identifier_refers_to_const_assertion).

Verify each finding against the current code and only fix it if needed.

Inline comments:
In `@crates/biome_js_analyze/src/lint/nursery/no_misleading_return_type.rs`:
- Around line 689-730: The match in is_wider_than currently ignores cases where
the inferred type is a Union or a Tuple, causing missed detections (e.g., string
vs "a" | "b" or [string, number] vs ["x",1] as const); add arms for (_,
TypeData::Union(inf_union)) and (_, TypeData::Tuple(inf_tuple)) that evaluate
whether every variant/element of the inferred union/tuple is narrower than the
annotated type by reusing/adding helper logic (e.g., call or add functions like
is_union_wider_when_inferred or is_tuple_wider to iterate variants/elements and
call is_wider_than/appropriate narrower checks with increased depth), and ensure
you handle literal-variant unions (Literal::String/Number/Boolean/BigInt/Object)
and const tuples by comparing each literal element to the annotated element
type.