feat/add-more-fields-responsive

[kriss145]

Summary

• Add side-specific repetitions and weights for strength exercises and set logs.
• Allow workout exercise targets to use repetitions or duration.
• Improve plan and workout structure navigation in Payload Admin, including exercise catalog selection.
• Show workout group protocol metadata and standardize rest duration labels.
• Reorganize training and sharing code into domain-oriented modules with explicit client-safe and server entry points.
• Align application types with generated Payload document types and separate plan document loading from plan tree building.
• Remove temporary backfill and normalization scripts while keeping seed and seed-export workflows.

Architecture

• Keep Payload collection documents as the source of truth for plan, workout, group, exercise row, and log types.
• Build the client-facing PlanTree in a pure transformation step after loading Payload documents.
• Move training components, admin modules, queries, constants, and formatters behind module public APIs.

Database

• Include generated migrations for the new workout exercise and set-log fields.
• Migration and backfill commands remain manual and were not run by the agent.

Testing

• yarn tsc --noEmit
• yarn lint - passes with 44 existing warnings in generated migration files.
• Production build not run.