Migration: add TODOs to impossible to migrate files

[henrikvilhelmberglund]

Describe the bug

Migration: afterUpdate left in file updated to use runes

import { afterUpdate } from "svelte"; is left after the migration which gives an error -

[plugin:vite-plugin-svelte] src/routes/ElectricPiano.svelte:6:10 afterUpdate cannot be used in runes mode
src/routes/ElectricPiano.svelte:6:10
4 |    import { ElectricPiano, getElectricPianoNames } from "smplr";
 5 |    // import { WebMidi } from "../../node_modules/webmidi/dist/esm/webmidi.esm.min.js";
 6 |    import { afterUpdate } from "svelte";
                            ^

I removed the import and replaced afterUpdate() with $effect().

Reproduction

https://github.com/henrikvilhelmberglund/keyboard/tree/old

Logs

No response

System Info

System:
    OS: Windows 10 10.0.19045
    CPU: (8) x64 Intel(R) Core(TM) i7-2600K CPU @ 3.40GHz
    Memory: 2.46 GB / 15.95 GB
  Binaries:
    Node: 20.14.0 - C:\Program Files\nodejs\node.EXE
    npm: 10.7.0 - C:\Program Files\nodejs\npm.CMD
    pnpm: 9.10.0 - C:\Program Files\nodejs\pnpm.CMD
    bun: 1.1.27 - ~\.bun\bin\bun.EXE
  Browsers:
    Edge: Chromium (127.0.2651.86)
    Internet Explorer: 11.0.19041.4355
  npmPackages:
    svelte: ^5.0.0-next.0 => 5.0.0-next.260

Severity

annoyance

[dummdidumm]

These files can't be migrated automatically, we need to add migration TODOs for these instead.

[paoloricciuti]

@henrikvilhelmberglund i took the liberty to change your title with the more appropriate action

[benmccann]

We should re-use the existing marker for any new TODOs (see also #13420)