feat(discord): add Neil Discord/Hermes skills

Full set of Neil skills for the LightInfoSys Solutions Team Discord assistant:

• neil-init v2.0 — conversational onboarding (AP/AR/Other use cases)
• neil-summary — summarize decisions and action items from channel history
• neil-blockers — list open blockers and their owners
• neil-draft — starter templates (kickoff, infra, AP checklist, MoM, etc.)
• neil-load-doc — load DRG/SOW/BRD into channel context for gap analysis
• neil-drg v1.0 — interactive DRG drafting with /neil-drg update section menu
• neil-email v1.0 — 10 client email types with full templates
• neil-deal-parse v1.0 — parse SOW → one-page finance deal summary
• neil-add-channel — admin skill to onboard new Discord channels

Skills live under src/skills/discord/ and run on the Hermes Agent gateway.