Require explicit data input in IQBCalculator and remove implicit fallback sample

[sanskar0627]

IQBCalculator.calculate_iqb_score currently accepts data=None and silently falls back to an internal sample dataset. This hides
missing-input errors and allows scores to be generated from placeholder data without the caller realizing it. The code already flags this as technical debt via a TODO to remove the default sample.

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Problem

• Calling calculate_iqb_score() without real measurement data still returns a score
• Integration bugs can pass unnoticed
• Results may be generated from fake/default values
• The method contract is misleading: data appears optional, but meaningful scoring requires real input

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Expected Behavior

• calculate_iqb_score requires explicit input data
• No internal fallback sample is used
• Callers and tests must pass real sample fixtures

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Proposed Change

• Make data a required parameter in the method signature
• Remove the internal sample dictionary fallback
• Update all affected tests that currently call the method without data
• Leave print_details behavior unchanged (out of scope)

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Why This Matters

• Enforces explicit API usage
• Prevents accidental scoring with placeholder data
• Surfaces integration errors early
• Improves correctness and reliability