Improve the self product and handling of patches

- The self product induces a p2 task with very restrictive version
ranges such that when that p2 task is composed with p2 tasks designed to
update the product, e.g., a milestone notification, the product cannot
actually update to a newer version.
- In general treat patches as optional (and greedy) given that an update
is often intended to make a patch obsolete.

https://github.com/orgs/eclipse-oomph/discussions/185

Author: merks

plugins/org.eclipse.oomph.p2.core/src/org/eclipse/oomph/p2/internal/core/ProfileTransactionImpl.java

@@ -1039,7 +1039,8 @@ private IInstallableUnit adjustProfileChangeRequest(final IProfileChangeRequest
         VersionRange versionRange = getCleanVersionRange(rootIU);
         IMatchExpression<IInstallableUnit> filter = rootIU.getFilter();
 
-        IRequirement rootRequirement = MetadataFactory.createRequirement(IInstallableUnit.NAMESPACE_IU_ID, id, versionRange, filter, false, false);
+        boolean isPatch = "true".equals(rootIU.getProperty(QueryUtil.PROP_TYPE_PATCH)); //$NON-NLS-1$
+        IRequirement rootRequirement = MetadataFactory.createRequirement(IInstallableUnit.NAMESPACE_IU_ID, id, versionRange, filter, isPatch, false);
         rootRequirements.add(rootRequirement);
         if (rootIU.isSingleton() || "true".equals(rootIU.getProperty(InstallableUnitDescription.PROP_TYPE_GROUP))) //$NON-NLS-1$
         {

plugins/org.eclipse.oomph.setup.core/src/org/eclipse/oomph/setup/internal/core/util/SelfProductCatalogURIHandlerImpl.java

@@ -216,13 +216,17 @@ private ProductCatalog create()
                 org.osgi.framework.Version osgiVersion = new org.osgi.framework.Version(version.toString());
                 int major = osgiVersion.getMajor();
                 int minor = osgiVersion.getMinor();
-                VersionRange versionRange = new VersionRange(Version.createOSGi(major, minor, 0), true, Version.createOSGi(major, minor + 1, 0), false);
+                VersionRange versionRange = new VersionRange(Version.createOSGi(major, minor, 0), true, Version.createOSGi(major + 1, 0, 0), false);
                 requirement.setVersionRange(versionRange);
               }
 
               requirement.setName(iu.getId());
               requirement.setMatchExpression(iu.getFilter());
               requirements.add(requirement);
+              if ("true".equals(iu.getProperty(QueryUtil.PROP_TYPE_PATCH))) //$NON-NLS-1$
+              {
+                requirement.setOptional(true);
+              }
             }
           }
         }