Fix offer list filter bug due to direction flip

Respect the direction parmeter;  do not give it meaning it does not
have.  If the user passes a 'buy' parameter, return buy offers.  Do
not misinterpret the param's intent.  The direction parameter's value
does not imply "buy=I'm a buyer, show me sell offers" or
"sell=I'm a seller, show me buy offers".

I got mixed up by looking at the UI.  If I want to sell BTC, I click
the SELL tab to view buy offers (maker as buyer).  If I want to buy
BTC, I click the BUY tab to view sell offers (maker as seller).

This change also fixes an offer list sorting bug.

The commit is in response to a requested changes in PR 4329:
bisq-network#4329 (review)

cli/src/main/java/bisq/cli/TableFormat.java

@@ -92,7 +92,7 @@ static String formatOfferTable(List<OfferInfo> offerInfo, String fiatCurrency) {
         return headerLine
                 + offerInfo.stream()
                 .map(o -> format(colDataFormat,
-                        o.getDirection().equals("BUY") ? "SELL" : "BUY",
+                        o.getDirection(),
                         formatOfferPrice(o.getPrice()),
                         formatAmountRange(o.getMinAmount(), o.getAmount()),
                         formatVolumeRange(o.getMinVolume(), o.getVolume()),

core/src/main/java/bisq/core/grpc/CoreOffersService.java

@@ -60,14 +60,19 @@ public CoreOffersService(CreateOfferService createOfferService,
 
     public List<Offer> getOffers(String direction, String fiatCurrencyCode) {
         List<Offer> offers = offerBookService.getOffers().stream()
-                .filter(o -> !o.getDirection().name().equalsIgnoreCase(direction)
-                        && o.getOfferPayload().getCounterCurrencyCode().equalsIgnoreCase(fiatCurrencyCode))
+                .filter(o -> {
+                    var offerOfWantedDirection = o.getDirection().name().equalsIgnoreCase(direction);
+                    var offerInWantedCurrency = o.getOfferPayload().getCounterCurrencyCode().equalsIgnoreCase(fiatCurrencyCode);
+                    return offerOfWantedDirection && offerInWantedCurrency;
+                })
                 .collect(Collectors.toList());
 
-        if (direction.equals(BUY.name()))
-            offers.sort(Comparator.comparing(Offer::getPrice));
-        else
+        // A buyer probably wants to see sell orders in price ascending order.
+        // A seller probably wants to see buy orders in price descending order.
+        if (direction.equalsIgnoreCase(BUY.name()))
             offers.sort(Comparator.comparing(Offer::getPrice).reversed());
+        else
+            offers.sort(Comparator.comparing(Offer::getPrice));
 
         return offers;
     }