apps/api AGENTS.md says a :id route shadows a single-segment route, but Fastify matches static routes first #1834

apps/api/AGENTS.md ("Adding a feature module") says a single-segment route such as
@Get('summary') can be shadowed by @Get(':id') on the same verb. perfectionist/sort-classes
orders handlers alphabetically, so a fixed route can end up declared below :id. The doc tells
readers to give such routes two segments.

The API runs on @nestjs/platform-fastify, whose router is find-my-way. Its README ("Match order")
matches a static node before a parametric one, whatever order the routes were registered in:

1. static
2. parametric node with static ending
3. parametric(regex)/multi-parametric
4. parametric
5. wildcard

So GET /v1/instrument-records/linear-model should reach @Get('linear-model') even when it is
declared below @Get(':id'). An ad-hoc Fastify check during the lint cleanup on the linting branch
found the same, but it was not committed.

If a request-level test confirms it

• Correct the paragraph in apps/api/AGENTS.md.
• Remove the file-level perfectionist/sort-classes disable at the top of
  apps/api/src/instrument-records/instrument-records.controller.ts. It exists only to keep
  @Get('linear-model') above @Get(':id'), and without it the handlers can sort.