feat: add personality editing to World Lab

[christopherjnelson]

Summary

• add server-authoritative editing for each active agent personality with shared runtime-validated API contracts
• add five bounded Personality Lab presets with explicit Edit, Apply, Cancel, character-count, and Custom states
• preserve active personalities across deterministic world reset and add a separately confirmed restore-default-personalities action
• keep completed observations immutable and clearly distinguish historical observation personality from active configuration
• reject personality mutations during active server turns with typed safe errors
• document session ownership, reset semantics, prompt subordination, security boundaries, testing, roadmap scope, and deferred work in ADR 0003 and supporting docs

Validation

The repository owner ran the complete local validation suite successfully:

• node --version
• pnpm --version
• pnpm install --frozen-lockfile
• pnpm format:check
• pnpm lint
• pnpm typecheck
• pnpm test
• pnpm build
• Chromium installation check as needed
• pnpm test:e2e

The repository owner also manually verified personality editing during genuine OpenRouter playback.

No local validation was rerun during publication.