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

Inline comments:
In `@crates/biome_js_type_info/src/resolver.rs`:
- Around line 819-835: The code creates a new TypeMember but only normalises
member.ty with resolved.apply_module_id_to_reference(...), leaving member.kind
(especially TypeMemberKind::IndexSignature(...)) containing raw references that
point to the wrong module; instead clone and normalise the entire member so keys
get the correct ResolverId. Update the construction of TypeMember to start from
a fully normalised member (e.g. clone a member that has had
apply_module_id_to_reference applied to all internal references) rather than
only normalising ty, and ensure whenever you call ResolvedTypeData.as_raw_data()
you pass or apply the correct ResolverId so subsequent resolution calls don’t
panic.
- Around line 958-976: In strip_undefined_from_member, resolve each union arm
via resolver.resolve_and_get before testing for undefined instead of comparing
raw TypeReference values to GLOBAL_UNDEFINED_ID; iterate union.0, call
resolver.resolve_and_get on each variant and drop arms whose resolved raw data
is TypeData::Primitive/Undefined (or resolves to GLOBAL_UNDEFINED_ID), then if
one arm remains set member.ty to that arm's TypeReference, else if some arms
were removed register a new Union via resolver.register_and_resolve and set
member.ty to TypeReference::from(new_id) (do not rebuild from raw union.0
directly); when calling resolved.as_raw_data() ensure you use the
ResolvedTypeData tied to the correct ResolverId (use the resolved value returned
from resolver.resolve_and_get) to preserve resolver context and avoid panics,
and handle the all-undefined case by registering an appropriate empty/undefined
union result rather than constructing an empty Union raw vector.

---

Outside diff comments:
In `@crates/biome_js_type_info/src/local_inference.rs`:
- Around line 2353-2363: The constructor parameter property synthesis currently
hardcodes is_optional to false inside the loop over constructor.parameters (the
branch matching FunctionParameter::Named(named_param)), which drops the
optionality; change the created TypeMember (Self { ... }) to set is_optional
using the NamedFunctionParameter flag (named_param.is_optional) instead of false
so the synthesized class member preserves the parameter's optionality when
constructing the member list in local_inference.rs.
- Around line 1881-1913: The JsPropertyClassMember branch currently passes a
hardcoded false for the readonly flag to Self::from_class_member_info; detect
readonly the same way as the TsPropertySignatureClassMember branch by examining
member.modifiers() for a TS readonly modifier (e.g. let is_readonly =
member.modifiers().into_iter().any(|m| m.as_ts_readonly_modifier().is_some());)
and pass is_readonly instead of false to from_class_member_info for
AnyJsClassMember::JsPropertyClassMember.

---

Nitpick comments:
In `@crates/biome_js_type_info/src/globals.rs`:
- Around line 40-41: Multiple places set identical default flags for TypeMember
(is_optional: false, is_readonly: false); introduce a small helper factory to
centralize those defaults and update all call sites. Add a constructor or
associated function like TypeMember::plain(name, ty) or a helper
plain_member(...) that sets is_optional and is_readonly to false and fills the
other common fields, then replace the repeated struct literals in globals.rs
(the places constructing TypeMember instances) to call that helper (e.g., use
TypeMember::plain or plain_member for the members currently using
is_optional/is_readonly flags).

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

Nitpick comments:
In `@crates/biome_js_analyze/tests/specs/nursery/useNullishCoalescing/invalid.ts`:
- Around line 85-87: Add a composed utility-type fixture that uses chained
mapped/utility types and the || operator to catch mapper-chaining regressions:
create a test similar to the existing `roOpt` case but declaring a variable like
`const composed: Readonly<Required<Partial<{ a: string | null }>>>` (or a
similarly named symbol) and then use `composed.a || "default"` (store result in
a variable such as `vComposed`) so the analyzer exercises composition of
Readonly/Required/Partial with a nullable property; add this to the same specs
directory as the other fixtures so the test suite validates the composed-type
behavior.

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

Inline comments:
In `@crates/biome_js_type_info/src/local_inference.rs`:
- Around line 2265-2267: The current member-kind encoding prioritizes is_static
over is_optional causing `static foo?: T` to be encoded as NamedStatic and lose
optional semantics; update the enum TypeMemberKind to include a
NamedStaticOptional variant (or otherwise ensure both flags are represented),
change from_class_member_info to emit NamedStaticOptional when both is_static
and is_optional are true, and then update TypeMember::is_optional(),
TypeMemberKind::is_static(), the formatter output for the new variant, and the
resolver transforms that handle Partial<T>/Required<T> so they respect the new
combined variant.

---

Duplicate comments:
In `@crates/biome_js_type_info/src/resolver.rs`:
- Around line 1020-1025: The current union filtering compares raw TypeReference
values and clones them directly, which misses aliased/normalized undefineds and
skips module ID normalization; change the loop over union.0 to first obtain
resolver_id via resolved.resolver_id(), apply module ID normalization to each
variant using resolver_id.apply_module_id_to_reference(), then call
resolver.resolve_and_get(&normalised) and filter out any resolved variant whose
as_raw_data() is TypeData::Undefined; finally, rebuild the filtered Vec by
mapping each original variant to the normalized (owned) TypeReference so the
reconstructed union uses normalized module IDs (use resolver.resolve_and_get(),
resolver_id.apply_module_id_to_reference(), TypeData::Undefined checks, and
avoid direct comparison to GLOBAL_UNDEFINED_ID).

---

Nitpick comments:
In `@crates/biome_module_graph/tests/spec_tests.rs`:
- Around line 2623-2646: The test currently only defines interface Config but
doesn't exercise utility-type synthesis; update the fixture inserted into
MemoryFileSystem in the test_optional_and_readonly_members test so the
/src/index.ts content also references Partial<Config>, Required<Config>, and
Readonly<Config> (for example create exported type aliases like ExportedPartial
= Partial<Config>, ExportedRequired = Required<Config>, ExportedReadonly =
Readonly<Config>) so ModuleGraph::update_graph_for_js_paths and
ModuleGraphSnapshot::new will synthesize those utility types and the snapshot
("test_optional_and_readonly_members") will capture the new synthesis path.