BDMS-592 Sidebar fixes

[jeremyzilar]

https://nmbgmr.atlassian.net/browse/BDMS-592

Why

• "Tables" and the top "NMBGMR Ocotillo" accordion added an extra layer of hierarchy and hid the whole nav when collapsed
• Users need Map, Wells, and other items visible at top level (Readiness review / BDMS-592)
• Breadcrumbs were cluttered by "Tables"; parent items had rounded borders that weren't desired

How

• resources/ocotillo.tsx: Removed "Tables" heading; flattened all table items to top-level; Map first; no Search in nav; no parent set so items are root-level
• resources/index.tsx: Removed the base "ocotillo" parent resource so the NMBGMR Ocotillo accordion is gone
• components/layout/sider.tsx: Cleared initial open state for removed structure; removed rounded borders and border from parent menu items (borderRadius: 0, border: 0)

Notes

• Search remains in the header only, not in the sidebar
• Breadcrumbs are driven by Refine's resource tree; they no longer show "Tables" now that the tree is flattened
• Observations, Apps, and Forms remain as collapsible sections with children