[v5.5] Fix result metadata and shadow-price rendering (align with upstream Variables.json)

[MahadevBalla]

Linked issue

• Closes [Task] Fix result metadata and shadow-price rendering from MUIO v5.5 #392
• Related [Task] Absorb selected MUIO v5.5 changes on origin/main #388

Existing related work reviewed

• Issues/PRs reviewed: [Task] Absorb selected MUIO v5.5 changes on origin/main #388, [Task] Pull the safe backend/runtime changes from MUIO v5.5 #390, [Task] Port the DataFile model/log diagnostics from MUIO v5.5 #391, feat: Port safe backend/runtime changes from MUIO v5.5  #397, feat: port DataFile diagnostics UI and ModelFile page from MUIO v5.5 #398, fix: adopt v5.5 result metadata and register missing result groups (#392) #405

Overlap assessment

• Classification: complementary and extending
• Overlapping items: [Task] Absorb selected MUIO v5.5 changes on origin/main #388 (parent tracker), feat: Port safe backend/runtime changes from MUIO v5.5  #397 (backend sync), fix: adopt v5.5 result metadata and register missing result groups (#392) #405 (result metadata alignment)
• Why this is not duplicate/superseded:
  • fix: adopt v5.5 result metadata and register missing result groups (#392) #405 aligns Variables.json and registers result groups at the metadata level
  • This PR completes that alignment in the frontend rendering layer, ensuring:
    • unitRule is applied in Pivot for result groups that define units via metadata (while keeping upstream Objective Value behavior as n/a)
    • Correct dimension handling for RYC, RYE, RYCn
    • Consistent behavior in updateParam and updateView
    • Proper empty-state handling (no stale pivot data)
  • Without these changes, metadata updates alone do not fully reflect in the UI

Why this PR should proceed

• [Task] Fix result metadata and shadow-price rendering from MUIO v5.5 #392 has no existing end-to-end frontend implementation
• Frontend was not aligned with upstream v5.5 metadata
• Without this, result rendering and units remain inconsistent

Summary

• What changed:
  • Adopted and applied upstream Variables.json as source of truth across Pivot rendering
  • Fixed unit rendering using unitRule instead of hardcoded n/a
  • Added support for RYCn (constraint group)
  • Fixed Pivot handling and field rendering for RYC, RYE, and RYCn groups
  • Synced updateView logic with updateParam
  • Cleared pivot data when no results exist (prevents stale UI)
• Why:
  • Previous implementation assumed Tech-based groups
  • New v5.5 groups use different dimensions (Comm, Emi, Con)
  • Pivot needed to respect upstream grouping and unit rules

Validation

• Tests added/updated (not applicable; UI layer, no existing test coverage)
• Validation steps documented
• Evidence attached (logs/screenshots/output as relevant)

Manual validation:

• Shadow price - Energy Balance (RYC)

  • commodity-based pivoting works
  • units render from metadata

• Shadow price - Emissions Limit (RYE)

  • emission-based pivoting works
  • units render from metadata

• Shadow price - UDC Inequality (RYCn)

  • constraint-based pivoting works
  • units render correctly

• Shadow price - UDC Equality (RYCn)

  • empty-state clears stale pivot/grid/chart content

• Number Of New Technology Units

  • number-based unit handling works

• Rechecked representative existing result paths:

  • New Capacity
  • New Storage Capacity
  • Input To New Capacity
  • Rate Of Activity

RYC – Shadow price - Energy Balance

RYCn – Shadow price - UDC Inequality

RYCn – Shadow price - UDC Equality (empty state)

RYT – Number Of New Technology Units

Documentation

• Docs updated in this PR (not applicable)
• Any setup/workflow changes reflected in repo docs

Scope check

• No unrelated refactors
• Implemented from a feature branch
• Change is deliverable without upstream OSeMOSYS/MUIO dependency
• Base repo/branch is EAPD-DRB/MUIOGO:main (not upstream)

Exception rationale

[parthdagia05]

405

[MahadevBalla]

Adding context wrt #405, this PR includes the metadata updates but also wires them into the Pivot layer (unitRule usage, group handling, empty state, etc.), so the changes are actually reflected in the UI.