Adds opt-in user profiles for swapping API keys, CLI binaries, and
permission modes between contexts (work/private/experiment/...).
Profile mode engages only when ~/.config/gnoma/profiles/ exists, so
existing single-config installations are untouched. Selection order:
--profile flag → default_profile in base config → fatal error.
Layering: defaults → ~/.config/gnoma/config.toml → profiles/<name>.toml
→ <projectRoot>/.gnoma/config.toml → env. Map sections merge per-key;
[[arms]] and [[mcp_servers]] merge by id/name; [[hooks]] appends.
Per-profile data: quality-<name>.json and sessions/<name>/ keep the
bandit and session list from cross-contaminating between profiles.
Profile names restricted to [A-Za-z0-9_-] to block --profile=../foo
path traversal into derived paths.
vikingowl
635dad660c