This PR introduces comprehensive documentation demystifying the Instability Index calculation used within Protly's Lab-Readiness Metrics. It provides clear, scientifically backed information on how the metric is computed and why the current architectural approach (using Biopython) is optimal.

Changes Included:

📄 New File: Added

instability_index.md
to the root directory, which covers:
The definition and UI thresholds ("Stable" < 40 vs "Unstable" >= 40) for the Instability Index.
An in-depth look at the Biopython (Bio.SeqUtils.ProtParam) module used for the computation.
The algorithmic logic (dipeptide occurrences) and the 1990 peer-reviewed scientific literature (Guruprasad K. et al.) it is based on.
An explanation of why using an industry-standard library is safer, faster, and more robust than hard-coding the 400 dipeptide weights manually.
External references to the original paper, Biopython documentation, and source code.
📝 README Update: Linked this new documentation directly in the

README.md
under the "Protein Analysis Pipeline" section for easy discovery by users and contributors.
Why is this needed? To ensure transparency and scientific rigor for our users. By documenting the specific library, its validation mechanisms, and the underlying mathematical/scientific basis of the stability score, we increase trust in the platform's analytical results. Furthermore, it aids future developers in understanding why Biopython is utilized instead of custom-built, hard-coded logic.

closes #8