Sync issue templates with project labels
## Description
The five issue templates in `.gitlab/issue_templates/` were using plain label
names (`~"Bug"`, `~"Feature"`, `~"Task"`, `~"Support"`, `~"Plan"`) that do not
exist in the project. The `/label` quick actions silently failed on issue
creation, so new issues were never auto-labelled by type. In addition, none of
the templates offered guidance on which component label to apply.
## Tasks
* [x] Replace broken label references with the correct scoped labels
(`category::bug`, `category::feature`, `category::task`,
`category::support`, `category::plan`) in all five templates.
* [x] Add a commented-out component label block to each template so reporters
can uncomment the relevant `aiCoreModule`, `aiAgent`, etc. label without
having to look up label names manually.
## Acceptance criteria
* All five templates apply the correct `category::` scoped label on issue
creation without any manual action from the reporter.
* Each template contains commented `/label` quick-action lines for all
15 component labels, with a clear instruction on how to activate one.
## Testing instructions
1. Open a new issue in this project and select any template.
2. Confirm the correct `category::` label is pre-filled.
3. Uncomment one component label line and submit — confirm the label is applied.
issue