Settings placeholder substitution (#164)

* Use text formatting for default factory values to produce dynamic names.
Header files contains duplicates of factory values defined in factory_settings.ini Removed them to simplify the code.

* Use text formatting for default factory values to produce dynamic names.
Header files contains duplicates of factory values defined in factory_settings.ini Removed them to simplify the code.

* Configured the WiFi host name to contain the device id by default

* Removed possibility to use placeholders for FACTORY_WIFI_SSID factory setting.

* Update README.md

Updated documentation

* Use text formatting for default factory values to produce dynamic names.
Header files contains duplicates of factory values defined in factory_settings.ini Removed them to simplify the code.

* Configured the WiFi host name to contain the device id by default

* Removed possibility to use placeholders for FACTORY_WIFI_SSID factory setting.

* Added a space to the end of the file to comply project code style

* fix typos
clang formatting
use 2 spaces in ini files
use ${platform}-${chip_id} for hostname
put chip id in brackets in AP SSID

* restore (and update) factory setting ifndefs

- this is so src can be built without an exaustive set build-time defines
- standardize ordering of defines: factory settings, paths, config

* format and modify comment

* escape spaces in pio defines
experiment with removing $'s from our format strings (they are being substituted with empty values by pio)

* fix formatting in readme
rename FactoryValue to SettingValue, put in own header
give example of direct usage of FactorySetting::format in README.md

* auto format

* use hash to delimit placeholders

* fix factory_settings.ini

* remove flash string helpers

* format ini file

* use MAC address instead of chip id for properly unique identifier

* use lower case hex encoding for unique id
use chip id and unique id for more secure secret

* fix comment

* Use random values for JWT secret
Arduino uses the ESP random number generator for "true random" numbers on both esp32 and esp8266
This makes a better JWT secret and may be useful for other factory defaults too
In addition a modification has been made to force the FSPersistance to save the file if applying defaults

* Don't use spaces in default AP SSID

* restore helpful comment in factory_settings.ini
fix default defines

Co-authored-by: kasedy <kasedy@gmail.com>

lib/framework/SecuritySettingsService.h

@@ -1,11 +1,16 @@
 #ifndef SecuritySettingsService_h
 #define SecuritySettingsService_h
 
+#include <SettingValue.h>
 #include <Features.h>
 #include <SecurityManager.h>
 #include <HttpEndpoint.h>
 #include <FSPersistence.h>
 
+#ifndef FACTORY_JWT_SECRET
+#define FACTORY_JWT_SECRET "#{random}-#{random}"
+#endif
+
 #ifndef FACTORY_ADMIN_USERNAME
 #define FACTORY_ADMIN_USERNAME "admin"
 #endif
@@ -48,7 +53,7 @@ class SecuritySettings {
 
   static StateUpdateResult update(JsonObject& root, SecuritySettings& settings) {
     // secret
-    settings.jwtSecret = root["jwt_secret"] | FACTORY_JWT_SECRET;
+    settings.jwtSecret = root["jwt_secret"] | SettingValue::format(FACTORY_JWT_SECRET);
 
     // users
     settings.users.clear();
@@ -103,7 +108,7 @@ class SecuritySettingsService : public SecurityManager {
   SecuritySettingsService(AsyncWebServer* server, FS* fs);
   ~SecuritySettingsService();
 
-  // minimal set of functions to support framework with security settings disabled  
+  // minimal set of functions to support framework with security settings disabled
   Authentication authenticateRequest(AsyncWebServerRequest* request);
   ArRequestFilterFunction filterRequest(AuthenticationPredicate predicate);
   ArRequestHandlerFunction wrapRequest(ArRequestHandlerFunction onRequest, AuthenticationPredicate predicate);