Add a data-quality warning for missing capacity

[AshutoshVJTI]

Context

Some queue rows may be missing capacity. Users should know whether a result is incomplete rather than assuming zero.

Scope

Add a small validation or UI warning for projects with missing capacity fields.

Acceptance criteria

• Missing capacity is not displayed as zero.
• UI or exported data makes the missing value explicit.
• Parser behavior is documented if touched.

Helpful files

• services/fetcher
• web/components
• web/lib