refactor(deps): migrate @angular/forms from v15.2.9 to v21.1.5

[digital-wizard48]

Changes

Version Bump

• Updated @angular/forms from ^15.2.9 to ^21.1.5 in package.json

Source Code Migration

settings_dialog_component.ts

• Removed deprecated as FormControl type assertions on FormControl instances
• Angular Forms v14+ introduced strictly-typed reactive forms (FormControl<T>), making the old as FormControl cast pattern unnecessary and discouraged
• reloadPeriodControl and paginationControl now use the typed FormControl<number> generic form, which provides better type safety and is the recommended pattern in Angular 14+

Notes

• The changelog for this release states "No user facing changes" — the primary migration work here is adopting the typed reactive forms pattern that was introduced in Angular 14 and is the standard in Angular 21
• All existing FormsModule, ReactiveFormsModule, Validators, and AbstractControl usages remain compatible and require no changes
• The ValidatorFn return type {[key: string]: any} | null in createIntegerValidator() continues to be valid

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This PR was auto-generated by Gittensor upgrade bot using Claude AI

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