Update to Typescript 6 / Jest 29

[alexdunae]

Prep for adding Stratakit components and general modernization.

Stratakit's optional render prop was being seen as required in TS 4, which is what prompted me to start this update.

• Update to Typescript 6 / Jest 29
• extracted a tsconfig.base.json to simplify config
• moved Jest TS config into jest.config.js - this lets us remove types: [node, jest] from the browser-targeting tsconfig files
• switched to moduleResolution: "bundler" since the previous node option is deprecated
• updated a few SVG imports to handle moduleResolution: "bundler"
• disabled Storybook's reactDogen for now (this shows TS types on Storybook) - it is not compatible with TS 6 but can be re-enabled when we update Storybook in Upgrade to Storybook 7 #108 - Storybook still shows props, just not with the full TS typings

---

This PR is based on #203 so CI isn't running automatically. Here are the manual runs... https://github.com/iTwin/admin-components-react/actions?query=branch%3Aalex%2Ftypescript6

[veekeys]

What do you mean by "adding stratakit components"?
If you plan to replace whole iTwinUI with StrataKit, that cannot be done as these components are used in BIC.

[veekeys]

Technically, this should be raised according to the peer deps of updated eslint deps:

There seems to be a bunch of peerDeps warnings in console too... not sure if some of those came with these updates

[alexdunae]

Going point, updated eslint peer deps.

Many of the peerDep warnings were from storybook - they were pre-existing but I added TS to the storybook package to remove most of the warnings.

require-from-string peerDep warning is an issue in Storybook

All the other peerDep warnings are Storybook-related and (I think) should be resolved by updating Storybook per #108

[veekeys]

any reason this was removed?
This changes interface from extent: { northEast: {}, southWest: {}}to extent: {northEast: undefined, southWest: undefined}. Have you checked if API accepts it correclty?

[alexdunae]

Spreading null/undefined results in an object.

❯ node
Welcome to Node.js v22.15.1.
Type ".help" for more information.
> { ...undefined }
{}
> { ...null }
{}

TSC 6 has better typechecking and says Right operand of ?? is unreachable because the left operand is never nullish.

The actual code will be semantically identical.

[veekeys]

What are the changes after ts update for consumers of these packages? Technically, its devDep change, shouldnt impact at all (then none), but with ts could be nuances..

[alexdunae]

I've been running diffs and the generated types output is unchanged other than removing /// <reference types="react" />

Archive.zip

❯ diff --ignore-all-space -u create-imodel-main-cjs-index.d.ts create-imodel-ts6-cjs-index.d.ts
❯ diff --ignore-all-space -u create-imodel-main-cjs-types.d.ts create-imodel-ts6-cjs-types.d.ts
❯ diff --ignore-all-space -u create-imodel-main-esm-index.d.ts create-imodel-ts6-esm-index.d.ts
❯ diff --ignore-all-space -u create-imodel-main-esm-types.d.ts create-imodel-ts6-esm-types.d.ts
❯ diff --ignore-all-space -u imodel-browser-main-cjs-index.d.ts imodel-browser-ts6-cjs-index.d.ts
❯ diff --ignore-all-space -u imodel-browser-main-cjs-types.d.ts imodel-browser-ts6-cjs-types.d.ts
--- imodel-browser-main-cjs-types.d.ts  2026-05-19 07:28:05
+++ imodel-browser-ts6-cjs-types.d.ts   2026-05-19 07:30:01
@@ -1,4 +1,3 @@
-/// <reference types="react" />
 import { CellProps } from "react-table";
 /** Full representation of the iModel. */
 export interface IModelFull {
❯ diff --ignore-all-space -u imodel-browser-main-esm-index.d.ts imodel-browser-ts6-esm-index.d.ts
❯ diff --ignore-all-space -u imodel-browser-main-esm-types.d.ts imodel-browser-ts6-esm-types.d.ts
--- imodel-browser-main-esm-types.d.ts  2026-05-19 07:28:05
+++ imodel-browser-ts6-esm-types.d.ts   2026-05-19 07:30:01
@@ -1,4 +1,3 @@
-/// <reference types="react" />
 import { CellProps } from "react-table";
 /** Full representation of the iModel. */
 export interface IModelFull {

[alexdunae]

I've set to empty comments and none - let me know if this aligns with how change files work in this repo.

[alexdunae]

What do you mean by "adding stratakit components"? If you plan to replace whole iTwinUI with StrataKit, that cannot be done as these components are used in BIC.

The plan is to add MUI components in parallel to existing iTwinUI components. So consumers will be able to import something like @itwin/admin-components-react/mui/iTwinGrid