reference/config.md: new page

Изменения

Address changes from picodata!913 (merged)

Версия: Picodata 24.3.0-99-gb7b01ab4 (picodata@b7b01ab4)

Spoiler

• https://git.picodata.io/picodata/picodata/picodata/-/commits/master/src/config.rs
• https://git.picodata.io/picodata/picodata/picodata/-/blob/master/src/config.rs

---

• Close #243 (closed), #255 (closed), #256 (closed), #257 (closed), #196 (closed)
• Changes should be cherry-picked to 24.2: no
• Staging:
  • https://docs.binary.picodata.io/picodata/asabirov_add_picodata_config/reference/config/
  • https://docs.binary.picodata.io/picodata/asabirov_add_picodata_config/reference/cli/#config_default
  • https://docs.binary.picodata.io/picodata/asabirov_add_picodata_config/reference/cli/#run
• Follow-up for picodata!893 (merged), picodata!907 (merged), picodata!913 (merged)