fix: compile @Injectable with coexisting PRIMARY decorators on the same class (#75)

Angular's `HandlerPrecedence` system allows `@Injectable` (SHARED) to coexist
with exactly one PRIMARY decorator (@component, @directive, @pipe, @NgModule).
The `else if` chain only processed one decorator per class, so @Injectable would
block @Pipe/@NgModule (or vice versa) when both were present.

Fix:
- Reorder chain: all PRIMARY decorators checked before SHARED @Injectable
- Add nested @Injectable checks inside each PRIMARY branch to generate ɵprov
- Mirror the same logic in the re-parse decorator span collection section

- Fix #65

Co-authored-by: Claude Opus 4.6 <noreply@anthropic.com>

Author: Brooooooklyn