refactor #1 + adding documentation (#36)

Reviewed-on: #36
Co-authored-by: Koda YeenBean <n122330@gmail.com>

wiki/Runtime-Flow.md

@@ -0,0 +1,76 @@
+# Runtime Flow
+
+The flow is generated alongside the call graph. Function names are validated
+against the current C sources so renamed or removed stages fail documentation
+checks.
+
+## Daemon scheduler
+
+```mermaid
+flowchart TD
+  start([main]) --> config[config_load]
+  config --> state[state_load]
+  state --> model[ufmodel_find]
+  model --> identity[Read LAN MAC, IP, and default gateway]
+  identity --> persist[state_save]
+  persist --> announceInit[announce_init when enabled]
+  announceInit --> loop{One-second main loop}
+  loop -->|announce due| announce[announce_send]
+  announce --> loop
+  loop -->|LLDP due| ports{For every model port}
+  ports --> lldp[lldp_send_frame]
+  lldp --> loop
+  loop -->|inform due| refresh[Refresh controller URL and device IP]
+  refresh --> inform[inform_send]
+  inform --> loop
+  loop -->|nothing due| sleep[sleep 1 second]
+  sleep --> loop
+```
+
+## Inform exchange
+
+```mermaid
+flowchart TD
+  send([inform_send]) --> url{inform URL available?}
+  url -->|no| error[Return an error]
+  url -->|yes| key{Device adopted?}
+  key -->|no| defaultKey[Use DEFAULT_AUTH_KEY]
+  key -->|yes| stateKey[Use persisted device key]
+  defaultKey --> payload[inform_build_payload]
+  stateKey --> payload
+  payload --> packet[inform_packet_build]
+  packet --> post[http_post]
+  post --> status{HTTP 200?}
+  status -->|no, first attempt| retry[Retry with alternate CBC or GCM cipher]
+  retry --> packet
+  status -->|no, final attempt| error
+  status -->|yes| decode[inform_packet_parse]
+  decode --> json[Parse controller JSON]
+  json --> handle[inform_handle_response]
+```
+
+## Controller response and provisioning
+
+```mermaid
+flowchart TD
+  response([inform_handle_response]) --> type{_type}
+  type -->|noop| done[No state change]
+  type -->|upgrade| version[Persist requested firmware version]
+  type -->|reboot or reset| reboot[reboot_openwrt]
+  type -->|cmd adopt| adopt[Persist key, URL, and adopted state]
+  type -->|setparam| params[Parse management parameters]
+  params --> legacy{system_cfg present?}
+  legacy -->|yes| legacyApply[wlan_apply_system_cfg]
+  legacyApply --> normalize[Build radio_table and vap_table JSON]
+  normalize --> apply[wlan_apply_config]
+  type -->|setstate| apply
+  apply --> ids[wlan_ensure_vap_ids]
+  ids --> clear[wlan_clear managed openuf_ VAPs]
+  clear --> radios[wlan_apply_radio for each band]
+  radios --> vaps[Create controller VAP sections]
+  vaps --> commit[Commit UCI and configure usteer]
+  commit --> start[Start and verify radios sequentially]
+  start --> result{Apply succeeded?}
+  result -->|yes| saved[Save cfgversion and config schema]
+  result -->|no| retryConfig[Reset cfgversion to 0]
+```