Move documentation related files into subdirectory to clean up root dir of project

docs/source/architecture/components/wfo/index.md

docs/source/architecture/config_decomposition/index.md

docs/source/architecture/dtap/acceptance.md

docs/source/architecture/dtap/development.md

docs/source/architecture/dtap/index.md

docs/source/architecture/dtap/production.md

docs/source/architecture/dtap/test.md

docs/source/architecture/index.md

.../assets/images/Architecture-WFO_Geant_specific.drawio.png

...rce/assets/images/Legacy_GAP_diagrams.overview.drawio.png

...ce/assets/images/TNC23_diagrams-AutomationTeam.drawio.png

...rce/assets/images/TNC23_diagrams-ConfigSlicing.drawio.png

.../assets/images/TNC23_diagrams-Current platform.drawio.png

...ce/assets/images/TNC23_diagrams-Separate Teams.drawio.png

...assets/images/TNC23_diagrams-Service_stitching.drawio.png

...sets/images/TNC23_diagrams-WFO-LSO_interaction.drawio.png

docs/source/assets/images/TNC23_diagrams-WFO_GAP.drawio.png

docs/source/assets/images/WFO_deploy_router.png

docs/source/assets/images/access_port_diagram.png

docs/source/assets/images/gap_architecture_diagram.png