feat(inspect): add --json flag for machine-readable stats output

[protosphinx]

Why

mcprec inspect currently outputs a colored timeline suitable for humans
but not for CI scripts or tooling that needs to parse transcript stats
programmatically. The diff command already supports --format json;
this PR brings the same machine-readable option to inspect.

What

• Add --json flag to the inspect CLI command in src/cli.ts
• When --json is set, load the transcript and output transcriptStats
  as indented JSON instead of the colored timeline display
• Import loadTranscript and transcriptStats in cli.ts (both already
  exported from their respective modules)

Tests

• New file test/inspect.json.test.ts (9 tests) covering JSON output shape:
  • Top-level keys exactly match the TranscriptStats interface
  • Stats round-trip through JSON.parse(JSON.stringify()) without loss
  • No undefined values (which JSON.stringify would silently drop)
  • All method count values are positive integers
  • methods object keys are ordered by count descending
  • Correct behavior for empty transcripts and response-only transcripts

Self-merge gate

• all CI checks pass
• LOC delta < 250 (167 lines: 12 in src/cli.ts + 131 in test/inspect.json.test.ts + 24 context/headers)
• no public-API surface change (src/index.ts not touched)
• no runtime-dependency additions (imports are from existing modules)
• no workflow file changes
• tests added (test/inspect.json.test.ts, 9 new tests)

🤖 Generated with Claude Code

https://claude.ai/code/session_01AwmG44UxpGyiZU1bshsELs

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Generated by Claude Code

[chatgpt-codex-connector]

Codex Review Summary

This comment shows the latest Codex review activity on this pull request.

Review	Status	Commit	Review trigger
📝 Code Review	✅ Completed 2026-09-08T16:14:29.383411Z	f8c5e4a	PR opened

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