Decompose json-helper.cjs god module

[dean0x]

Context

scripts/hooks/json-helper.cjs is 1,837 lines with 29 switch cases. PR #193 extracted sidecar-ops.cjs as the first domain module using the handle(command, args, cwd) => boolean pattern.

Pattern

Each extraction follows the established routing pattern:

// In json-helper.cjs — lazy-loaded, routed before the main switch
if (op === 'some-operation') {
  const someOps = require('./lib/some-ops.cjs');
  if (someOps.handle(op, args, process.cwd())) {
    process.exit(0);
  }
}

Extraction Candidates

Logical groupings by domain:

• Learning operations — process-observations, render-ready, reconcile-manifest, merge-observation, temporal-decay, filter-observations, learning-created, learning-new
• Knowledge operations — knowledge-append, read-sidecar (done)
• Session/memory operations — session-output, prompt-output, backup-construct
• JSON utilities — get-field, get-field-file, validate, compact, update-field, update-fields, construct

Acceptance Criteria

• Each extracted module follows handle(command, args, cwd) => boolean
• Lazy-loaded via conditional require() — no eager top-level imports
• All existing tests pass without modification
• json-helper.cjs shrinks proportionally with each extraction