[#13452] Update tsconfig to follow fresh Angular 20 project, enforce strictTemplates

[wkurniawan07]

Fixes #13452

Outline of Solution

1. Reworked tsconfig.json, tsconfig.app.json, and tsconfig.spec.json to be based on a fresh Angular 20.3 project.
2. Enforced strictTemplates=true and fixed all violations
3. Some frontend files unnecessary have 755 permission; they have been reverted back to 644

[Copilot]

Pull request overview

This PR updates the Angular TypeScript configuration to align with Angular 20 defaults and enforces strict template type checking. The changes modernize the build configuration and introduce type safety improvements throughout the codebase.

Changes:

• Updated TypeScript configuration files to follow Angular 20 conventions
• Introduced helper functions for type-safe event target casting
• Added type assertion utilities for question and response details
• Fixed template type errors exposed by strict template checking

Reviewed changes

Copilot reviewed 97 out of 107 changed files in this pull request and generated 5 comments.

Show a summary per file

File	Description
tsconfig.spec.json	Removed redundant compiler options inherited from base config
tsconfig.app.json	Updated file inclusion patterns to match Angular 20 conventions
src/web/types/event-target-caster.ts	Added helper functions for type-safe DOM element casting
src/web/types/question-details-impl/question-details-caster.ts	Added utilities for type-safe question details casting
src/web/types/response-details-impl/response-details-caster.ts	Added utilities for type-safe response details casting
Multiple .component.ts files	Updated to use inject() pattern and event target casting helpers
Multiple .component.html files	Fixed template bindings to satisfy strict type checking
Multiple .snap files	Updated test snapshots to reflect component changes

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[samuelfangjw]

Thanks for this, appreciate the attention to detail.

I still see a few warnings on console, likely caused be stricter checks. Don't know if you want to include it in this PR.

NG8107: The left side of this optional chain operation does not include 'null' or 'undefined' in its type, therefore the '?.' operator can be replaced with the '.' operator. [plugin angular-compiler]

    src/web/app/components/course-edit-form/course-edit-form.component.html:109:95:
      109 │ ...btn-success" type="submit" [disabled]="form?.invalid || isSaving"
          ╵                                                 ~~~~~~~   

among others.

[samuelfangjw]

Thanks for the changes!