Implement format parser end-to-end

implement input-format parser end-to-end from issue

implementing new data parsers with 0-mutation hardening

• · args: JSON object or array per workflow
• · format issue: GitHub issue URL or id string

• · structured result JSON

• · agent orchestration
• · build/compilation tools
• · GitHub CLI
• · GitHub issue API

• · return schema defined and enforced
• · phase logging initialized
• · build env configured

• · agent null on error/skip/rate-limit

• · strict return schema enforced
• · test suite + clippy validation