Proof mode docs: COFE → OFE, CMRA → camera.

ProofMode.md

@@ -59,7 +59,7 @@ Introduction of logical connectives
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 - `iPureIntro` : turn a pure goal into a Coq goal. This tactic works for goals
-  of the shape `⌜φ⌝`, `a ≡ b` on discrete COFEs, and `✓ a` on discrete CMRAs.
+  of the shape `⌜φ⌝`, `a ≡ b` on discrete OFEs, and `✓ a` on discrete cameras.
 
 - `iLeft` : left introduction of disjunction.
 - `iRight` : right introduction of disjunction.