Repair cross-group README links whose targets changed groups
(ui/jsonrpc, ui/app-boot -> examples; examples/* -> ui seams),
re-record the bilingual-pair consistency hashes for the docs the
rename touched on both language sides, and condense the AGENTS.md and
packages/README.md group entries. The packages/README ceiling rises
710 -> 760 for the mandated new examples/ hierarchy row (5% headroom).