Opportunity card: add match status field

[nadavosa]

Summary

Opportunity cards are missing a match status field. This status is derived entirely from the volunteer section already present on each opportunity profile — no new BE endpoint is needed.

Status values

Value	Display label	Condition
no_match	No match	Default — no volunteers linked to this opportunity
pending_match	Pending match	At least one volunteer has this opportunity in their Pending section (even if others are matched)
matched	Matched	Volunteer(s) are in the Matched section for this opportunity
past	Past	Volunteer(s) are in the Past section — the number of active volunteers no longer covers the number of volunteers needed

Logic notes

• The status is computed from the volunteer section data that already exists on the opportunity profile
• Priority order when multiple volunteers exist: if any volunteer is Pending, show Pending match over Matched
• Past applies when the covered volunteer count drops below the required headcount
• No match is the fallback when no volunteer is associated at all

Placement

The match status field should appear visually below "Current status" and above "Volunteer type" on the opportunity card.

Scope

FE only — derive and display the status from the existing volunteer section on the opportunity card (list view + detail view)

[muslimalfatih]

Taking this one. Will start working on it shortly