feat(diary): channels, components and config/log.yaml

- stderr and null drivers; per-component levels from log.components
- SUMMER_LOG__ overrides parse as strings and overlay the defaults key by key
- Validation names the key: driver, format, level, days, stack children and cycles, daily path outside the root
- summer new writes config/log.yaml (stack of console and daily, river warn, http info)
- docs/services/logging.md: channels, config/log.yaml, component loggers, daily files, redaction
- Log keys in the configuration docs; ExampleFor backs the docs snippet

docs/setup/configuration.md

@@ -37,7 +37,7 @@ Any key can be overridden with an environment variable. Take the dot path, repla
 
 A `.env` file next to the `config/` directory supplies `KEY=VALUE` lines for variables that are not already set in the real environment. Keep secrets in the environment or in `.env`, never in committed YAML.
 
-Environment values are strings. Keys that must be numbers, such as `http.body_limits.default_bytes`, belong in a YAML file.
+Environment values are strings. Keys that must be numbers, such as `http.body_limits.default_bytes`, belong in a YAML file. The `log.*` keys accept strings: `SUMMER_LOG__CHANNELS__DAILY__DAYS=30` keeps daily log files for 30 days, and `SUMMER_LOG__CHANNELS__STACK__CHANNELS=console,daily` sets a list.
 
 The layers merge in this order, each overriding the ones before it: plugin defaults, `config/*.yaml`, `config/env/<environment>/*.yaml`, `SUMMER_` variables, then runtime overrides that a command saved to `config/env/<environment>/overrides.yaml`.
 
@@ -59,6 +59,7 @@ These are the keys most applications set. Each module's reference page lists all
 | `cache.driver`, `cache.prefix`, `cache.memory.max_entries` | The cache driver (`memory`, the default, or `redis`), the key prefix (default from `app.name`) and the memory driver's size bound (default 10000). | [cooler](../../modules/cooler/README.md) |
 | `site_cache.purge_url`, `site_cache.purge_token` | The host site's page-cache purge route and its bearer token (at least 32 characters). Set both or neither; http only to a loopback host. Keep the token in `SUMMER_SITE_CACHE__PURGE_TOKEN`. | [cooler](../../modules/cooler/README.md) |
 | `redis.url` | Redis URL (`redis://`, `rediss://` or `unix://`), required when a Redis cache or rate-limit store is selected. Keep it in `SUMMER_REDIS__URL` when it carries a password. | [cooler](../../modules/cooler/README.md) |
+| `log.default`, `log.level`, `log.channels.*`, `log.components.*` | Logging: the default channel (`stack` of `console` and `daily`), the global level (`info`), the channels (`driver`, `level`, `format`, `path`, `days`, `channels`) and per-component levels. Daily files go to `storage/logs/` and are kept 14 days. See [Logging](../services/logging.md). | [diary](../../modules/diary/README.md) |
 | `http.access_log` | Logs one record per request with method, matched route pattern, status and duration. Defaults to `false`. | [surf](../../modules/surf/README.md) |
 | `http.error_pages.enabled` | HTML error pages for browser navigations (defaults to `true`); request details appear when `app.debug` is true or outside production. | [surf](../../modules/surf/README.md) |
 | `storage.uploads.bucket_url` | Uploads bucket, `file://`, `mem://` or `s3://` (the last only in a binary built with the `summercms_s3` tag from `build.tags` in `summer.yaml`; credentials from the AWS environment). Required by `serve`. | [lagoon](../../modules/lagoon/README.md) |