Migrate deprecated tsconfig options before TypeScript 7 (target, moduleResolution, baseUrl)

[yoganandaness]

Context

As part of the TypeScript 6 upgrade (frontend), three compilerOptions in apps/frontend/tsconfig.json are now deprecated and will be removed in TypeScript 7. To keep TS 6 compiling, we currently suppress the deprecation errors with:

"ignoreDeprecations": "6.0"

This is a temporary shim. Before upgrading to TS 7, these options must be actually migrated and the ignoreDeprecations line removed.

Options to migrate

Current	Target replacement	Notes / risk
"target": "es5"	"es2020" (or higher)	Changes emitted JS (no more down-leveling). Vite controls the real build target, so mostly affects type-checking. Confirm browser-support matrix.
"moduleResolution": "node"	"bundler"	Matches our Vite setup. May surface import-path issues (exports fields, extensions).
"baseUrl": "src"	"paths"	Highest risk. paths only affects the type-checker; Vite resolves separately, so we also need resolve.alias (or vite-tsconfig-paths) to match, or runtime imports break.

Acceptance criteria

• Replace target: es5 with es2020+
• Replace moduleResolution: node with bundler
• Replace baseUrl: src with explicit paths (+ matching Vite alias config)
• Remove "ignoreDeprecations": "6.0" from apps/frontend/tsconfig.json
• tsc --noEmit passes with no deprecation errors
• Production build succeeds and a browser smoke test passes

Suggested approach

Do this as its own PR (cut from develop), separate from the TS 6 upgrade branch. Migrate one option at a time, verifying tsc --noEmit + a real build after each.

Reference: // Remove once those move to es2020 / bundler / paths comment in apps/frontend/tsconfig.json.

[yoganandaness]

Note: The frontend TS6 upgrade is not yet released into develop. It is still the ongoing PR. UserOfficeProject/user-office-core#1745