docs(config): revamp configuration documentation for the two-category model
Rewrites the configuration docs around the post-#415 model (Bootstrap vs
Operational categories, plus the still-live env > file > db precedence):
- Configuration-Model (new): the concept hub — the two categories, how values
are resolved (categories decide WHERE a value may live; precedence decides
WHICH wins), vault://env://file:// secret references, the secret-vs-bootstrap
orthogonality with Timmy as the worked example, hot vs static, visibility,
the three bootstrap-only config files, required settings.
- Configuring-Local-Development (new): dev setup, config-example -> -development,
TMI_* overrides, the OAuth stub + login_hint, operational settings in dev.
- Bootstrapping-Production (new): the bootstrap-only skeleton, secret wiring +
three-phase resolution, first-run DB seeding, --import-legacy migration,
platform notes (OCI/ADB, Heroku, Kubernetes), worker bootstrap, a checklist.
- Managing-Operational-Settings (new, replaces Configuration-Management):
/admin/settings CRUD + reencrypt, the source field + 409-on-config-controlled,
runtime reconfiguration of Timmy/content sources, dbtool import flags.
- Configuration-Reference (rewritten): generated from the classification
registry via 'make generate-config-docs' — drift-guarded, never hand-edited.
- Configuration-Management and Config-Migration-Guide retired to redirect stubs.
- Sidebar updated; Content-Extractors page cross-linked.
Pairs with the dev/1.4.0 generator (EnvVar field + cmd/genconfigdocs).