feat: LAFS default MVI 'standard' → 'minimal' (agent-first protocol)

The LAFS resolveFieldExtraction() now defaults to 'minimal' when no
--mvi flag is passed. This is the protocol-level change that makes
all CLEO consumers agent-optimized by default.

Minimal format uses compact field names:
  ok (success), r (result), _m (_meta), op (operation), rid (requestId)

Users can still get full output with --mvi standard or --mvi full.

Verified: local build outputs 1405 bytes vs 1648 bytes for task show
(15% envelope savings, more on larger payloads).

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

Author: kryptobaseddev

packages/lafs/src/fieldExtraction.ts

@@ -49,7 +49,7 @@ export function resolveFieldExtraction(
 
   // 'custom' is server-set (§9.1) — not a client-requestable level
   const validMvi = isMVILevel(input.mviFlag) && input.mviFlag !== 'custom';
-  const mvi: MVILevel = validMvi ? input.mviFlag as MVILevel : 'standard';
+  const mvi: MVILevel = validMvi ? input.mviFlag as MVILevel : 'minimal';
   const mviSource: FieldExtractionResolution['mviSource'] = validMvi ? 'flag' : 'default';
 
   const hasFields = (fields?.length ?? 0) > 0;