Complete Task 7 prep: add series setup to NFO repair test

Remove obsolete Task 6 from docs (logging download - either fixed or abandoned).
Add series to library before repair call in test - ensures series exists in DB.

tests/robot/api/nfo.robot

@@ -27,6 +27,10 @@ Get NFO Diagnostics
 # ---------------------------------------------------------------------------
 Repair NFO For Series
     [Documentation]    Trigger NFO repair for a specific series.
+    ...    First add the series to the library so it exists in the database.
+    ${add_resp}=    Add Series    https://aniworld.to/anime/stream/attack-on-titan    Attack on Titan    2013
+    Response Should Have Status    ${add_resp}    202
+    ...    NOW call repair on the known series
     ${resp}=    Repair Nfo    attack-on-titan
     Response Should Have Status    ${resp}    200
     Response Should Be Valid JSON    ${resp}