Context is the reason this is not ambiguous, and should not be misunderstood as ‘ses bonnes idées’ (her) good ideas, instead of ‘ces bonnes idées’ (these/those good ideas).

This is an exchange directly between 2 individuals - either the formal ‘vous’ or informal ‘tu’ would be be the address used.

If this phrase was meant to express ‘I have noted all your good ideas’, it would be ‘tes bonnes idées’ or ‘vos bonnes idées’.

 Anne is thanking Joséphine at the end - ‘toutes ses bonnes idées’ would only be a possibility if she was addressing someone other than Joséphine and telling them about ‘all her (Joséphine’s) good ideas’. 

In this context ‘ces bonnes idées’ is the way to interpret what is said. 

Common mistakes with mon/ma/mes, ton/ta/tes and son/sa/ses (French Possessive Adjectives) 

Notre/nos/votre/vos/leur/leurs = our/your/their (French Possessive Adjectives) 

Ce/cet/cette and ces = this/that and these/those (French Demonstrative Adjectives)