Investigate + surface the untagged /pay whale economy ($17M, highly concentrated, no audit trail)

Context (revisit item from an economy-data review)

All no_src ledger flow is in-game /pay (see PAR-145): $16.99M / 14,817 transfers, untagged and almost entirely unannotated ("Payment from X to Y", no memo). It's the most opaque layer of the economy and it's highly concentrated among a handful of whales — exactly where OTC deals, informal banking, loans, or RMT cash-outs would hide. We said we'd revisit; this issue captures the data so far.

What the data shows (12-day window)

Net senders (push money out via /pay):

• 59nico −$2,525,236 (sent $2.54M, received $18k) — the hub. The $3.45M ChestShop magnate recycles shop revenue out via /pay in structured repeating amounts ($335k×2, $200k×2, $400k) to Fletchingrs, summerock, Lbozo13, PandaHacker5498 — looks like wholesale buying / payroll / a supplier pipe.
• razorsharpbread −$663k, notthelesser −$592k, Multiman155 −$587k, xSyncx −$550k, Bardiya_King −$357k, xEndeavour −$252k — mostly pure senders (received ~$0).

Net receivers (accumulate via /pay):

• Fletchingrs +$823k, summerock +$779k, Lbozo13 +$578k, 1vtmdeveloper +$554k, fluffywaafelz +$510k, GnomeWhisperer +$469k, poy1 +$395k, Musclebound +$354k.

Pattern: pure-sender → fintech-receiver looks like deposits into player-run funds/banks that settle via /pay instead of the REST API (e.g. razorsharpbread→fluffywaafelz $650k; xSyncx→GnomeWhisperer $550k; notthelesser→Pikaonly $350k +→poy1 $157k). A chunk of "top earner" income is just received /pay, not productive output.

To do when we revisit

1. Visibility (explorer): a money-flow / net-position view for peer payments (top senders/receivers, largest transfers, bilateral pipes) — depends on PAR-145 tagging to separate /pay cleanly. Optionally flag unusually large/structured peer transfers.
2. Investigate the concentration: is the 59nico hub legit wholesale/payroll vs an alt/front? Are the pure-sender→receiver pairs alt-account self-dealing (shared login patterns, shared properties/firms) or genuine deposits into player banks?
3. Decide whether large untagged peer payments warrant a lightweight audit trail / memo nudge for oversight.

Acceptance

• A documented read on what the /pay whale layer actually is (wholesale vs banking vs self-dealing), and a decision on whether/how to surface it in the explorer.

Sibling of PAR-145 (the tagging fix that makes this analyzable).