Parallel, intercepted catchall routes provided wrong params

### Link to the code that reproduces this issue https://github.com/Drewsapple/repro-intercept-catchall ### To Reproduce 1. Start the app (`next dev` or `next build && next start`) 2. navigate to `/reproduction` 3. click the link to `/reproduction/double/double` 4. refresh the page or otherwise load the same route so navigation is not intercepted ### Current vs. Expected behavior When the default export from `(.)[...catchall]/page.tsx` is loaded, the params object passed is are follows: Navigating to `/reproduction/single` ``` {"catchall":["single"]} ``` Navigating to `/reproduction/double/double` ``` {"catchall":["doubledouble"]} ``` Instead of the route segments being concatenated as strings, they should be concatenated as array elements, i.e. ``` {"catchall":["double","double"]} ``` ### Provide environment information ```bash Operating System: Platform: linux Arch: x64 Version: #1 SMP PREEMPT_DYNAMIC Debian 6.11.6-1 (2024-11-04) Available memory (MB): 15748 Available CPU cores: 8 Binaries: Node: 20.11.1 npm: 10.9.0 Yarn: N/A pnpm: 9.14.2 Relevant Packages: next: 14.2.18 // An outdated version detected (latest is 15.0.3), upgrade is highly recommended! eslint-config-next: N/A react: 18.3.1 react-dom: 18.3.1 typescript: 5.6.3 Next.js Config: output: N/A ``` ### Which area(s) are affected? (Select all that apply) Parallel & Intercepting Routes ### Which stage(s) are affected? (Select all that apply) next dev (local), next start (local) ### Additional context I tried this in v14.2.14 as well, to see if it was a regression introduced by #65063 in v14.2.15, but the behavior was the same. In v15.0.3 (with awaited params), the catchall group doesn't intercept a navigation with multiple path segments at all. This modification is tracked in the `v15.0.3` branch of the reproduction repo.