Implement missing AAS REST API endpoints

[ptrstn]

Several endpoints defined in the BaSyx AAS REST API are currently missing in the current implementatio. To achieve full coverage and spec-compliance, these need to be added.

Method	Endpoint	Input type	Output type	Status code (expected)	Other Codes
GET	/concept-descriptions	None	dict	200	400,401,403,500
POST	/concept-descriptions	dict	dict	201	200,400,401,403,409,500
DELETE	/concept-descriptions/{cdIdentifier}	None	None	204	200,400,401,403,404,500
GET	/concept-descriptions/{cdIdentifier}	None	dict	200	400,401,403,404,500
PUT	/concept-descriptions/{cdIdentifier}	dict	None	204	200,400,401,403,404,500
GET	/description	None	dict	200	403,default
GET	/serialization	None	dict	200	400,401,403,404,500
GET	/shells/{aasIdentifier}/asset-information	None	dict	200	400,401,403,404,500
PUT	/shells/{aasIdentifier}/asset-information	dict	None	204	200,400,401,403,404,500
DELETE	/shells/{aasIdentifier}/asset-information/thumbnail	None	dict	200	400,401,403,404,500
GET	/shells/{aasIdentifier}/asset-information/thumbnail	None	dict	200	400,401,403,404,500
PUT	/shells/{aasIdentifier}/asset-information/thumbnail	file bytes multipart	None	204	200,400,401,403,404,500
DELETE	/submodels/{submodelIdentifier}/submodel-elements/{idShortPath}/attachment	None	dict	200	400,401,403,404,500
GET	/submodels/{submodelIdentifier}/submodel-elements/{idShortPath}/attachment	None	dict	200	400,401,403,404,500
PUT	/submodels/{submodelIdentifier}/submodel-elements/{idShortPath}/attachment	file bytes multipart	None	204	200,400,401,403,404,500
POST	/submodels/{submodelIdentifier}/submodel-elements/{idShortPath}/invoke	dict	dict	200	400,401,403,404,405,500