Proposing several changes

• regrouping workflow scripts
• reorganization of README sections (added some as suggestions too)
• added badges generated by HUMG (+ integrated in README)
• HUMG also updated metrics in htr-united.yml
• added a CC-BY 4.0 LICENSE to match info in README, although I would suggest clarifying what applies to what (right now you say the transcription are copyright free but the image are under Heidelberg's library copyright, yet the dataset is under CC-BY)
• added placeholder for a folder of static images, to add illustrations of the dataset, the transcription guidelines and any other logos
• added character table as generated by chocomufin

CITATION.cff

+# This CITATION.cff file was generated with cffinit.
+# Visit https://bit.ly/cffinit to generate yours today!
+
+cff-version: 1.2.0
+title: >-
+  Codex palatinus graecus 23 - Ground Truth Dataset Medieval
+  Greek Manuscripts
+message: >-
+  If you use this dataset, please cite it using the metadata
+  from this file.
+type: dataset
+authors:
+  - given-names: Maxime
+    family-names: Guénette
+    orcid: 'https://orcid.org/0009-0006-2076-1220'
+  - given-names: Mathilde
+    family-names: Verstraete
+    orcid: 'https://orcid.org/0000-0003-1642-8610'
+  - given-names: Alix
+    family-names: Chagué
+    orcid: 'https://orcid.org/0000-0002-0136-4434'
+  - given-names: Marcello
+    family-names: Vitali-Rosati
+    orcid: 'https://orcid.org/0000-0001-6424-3229'
+repository-code: 'https://gitlab.huma-num.fr/ecrinum/anthologia/htr_cpgr23'
+keywords:
+  - HTR
+  - ground-truth
+  - greek
+  - medieval manuscript
+  - palatine anthology
+license: CC-BY-4.0