refactor: hypothetical extraction and R6 class

[albersonmiranda]

What type of PR is this? (check all applicable)

• [x] Refactor
• [ ] Feature
• [x] Bug Fix
• [ ] Optimization
• [x] Documentation Update

Description

Refactor R6 class adding slots to aggregate final demand and added value vectors, and updating via update_*_matrix() method, instead of active binding that didn't worked as argument for computations. Also update getting started vignette accordanly.

Related Tickets & Documents

• Closes #55
• Closes #33
• Closes #10

Added/updated tests?

Goal is code coverage percentage at 80% and above.

• [ ] Yes
• [x] No, and this is why: testes not set yet
• [ ] I need help with writing tests

Pre-merge checklist

• [x] PR title follows semantic commit guidelines (e.g., fix:, feat:, refactor:, test:, docs:)

Pre-release checklist

• [ ] Bump version (both Rust & R packages, accordingly)
• [x] Update NEWS.md
• [x] Precompiled Windows binaries
• [x] Precompiled Linux binaries