AYUD-123: vendor Pluto sort-core + make PersonasTable/NecesidadesOverviewTable sortable

AYUD-123 (fleet sortable-table adoption, bs-mr4rmdgg241 decision): vendor Pluto's canonical sort-core BYTE-FOR-BYTE from gdrive /gdrive/projects/evolutiva/pluto/sort-primitive/ (sort-utils.ts 88 lines + use-sortable-table.ts 95 lines, Pluto SHA 6f3243f v2.0.1) into ayudarg's lib/ + hooks/ (keep the canonical-SSOT headers, do NOT edit — Pluto owns, bin-whey-cc syncs). Then wire the two currently-static tables — PersonasTable + NecesidadesOverviewTable — to the hook, building ayudarg's OWN SCSS keyboard-accessible sortable <th> head (the head does NOT travel per the decision). Respect the 3 edges: tri-state asc→desc→CLEAR, deterministic id-tiebreak, nullsLast opt-in. Client sort (<500 rows). Mobile-first, 44px targets.