Fix vault fee display tooltips

[miohtama]

Why

Vault listing and detail pages needed clearer fee metadata. Group listings with an Avg. APY column now explain that the value is TVL-weighted over the last 30 days. Vault detail fee tables need to display contractual gross fees while keeping net return values sourced from the existing net return data, and internalised-fee vaults need explicit copy explaining why gross and net returns may match.

Lessons learnt

Internalised vault fees can already be reflected in the share price data, so the frontend should not infer a fee adjustment from the displayed contractual fee. The UI needs to distinguish display-only gross fee schedules from net return fields supplied by the vault dataset.

Summary

• Added a tooltip-backed Avg. APY header to the shared vault group table.
• Switched vault detail fee rows to display gross fee values while leaving net return rows on net return fields.
• Added internalised-fee explanatory tooltip copy and a table disclaimer for internalised-fee vaults.
• Added focused regression coverage for fee display and internalised-fee messaging.