Deprecate processCcd subset.

The name "processCcd" is a throwback to the Gen 2 ProcessCcdTask, and
is not intuitive for new users who've only known Gen 3. The replacement
name apPipeSingleFrame conveys the term "single-frame processing"
(which is still in use) while distinguishing between the subset of
ApPipe and the standalone SingleFrame pipeline (which are conceptually
different enough that they must not be mixed up).

pipelines/_ingredients/ApPipe.yaml

@@ -88,12 +88,21 @@ tasks:
       connections.coaddName: parameters.coaddName
 
 subsets:
+  apPipeSingleFrame:
+    subset:
+      - isr
+      - calibrateImage
+      - initialPviCore
+    description: >-
+      The prompt ApPipe tasks that make up single-frame processing. Not to be confused with the
+      SingleFrame.yaml pipeline, which does more than just ApPipe single frame processing, and
+      is designed as a standalone alternative to ApPipe.yaml.
   processCcd:
     subset:
       - isr
       - calibrateImage
       - initialPviCore
-    description: The tasks that make up single-frame processing.
+    description: Deprecated alias for apPipeSingleFrame, will be removed after v29.
   apPipe:
     subset:
       - loadDiaCatalogs

pipelines/_ingredients/ApPipeWithFakes.yaml

@@ -123,12 +123,21 @@ tasks:
       connections.fakesType: parameters.fakesType
       connections.science: fakes_initial_pvi
 subsets:
+  apPipeSingleFrame:
+    subset:
+      - isr
+      - calibrateImage
+      - initialPviCore
+    description: >-
+      The prompt ApPipe tasks that make up single-frame processing. Not to be confused with the
+      SingleFrame.yaml pipeline, which does more than just ApPipe single frame processing, and
+      is designed as a standalone alternative to ApPipeWithFakes.yaml.
   processCcd:
     subset:
       - isr
       - calibrateImage
       - initialPviCore
-    description: 'The tasks that make up single-frame processing.'
+    description: Deprecated alias for apPipeSingleFrame, will be removed after v29.
   apPipe:
     subset:
       - isr
@@ -195,11 +204,16 @@ subsets:
     description: >
       Tasks for QA and other non-real-time processing.
       Requires prompt subset to be run first.
+  injected_apPipeSingleFrame:
+    subset:
+    - inject_visit
+    description: >-
+      All tasks from the 'apPipeSingleFrame' subset impacted by source injection.
   injected_processCcd:
     subset:
     - inject_visit
     description: >
-      All tasks from the 'processCcd' subset impacted by source injection.
+      Deprecated alias for injected_apPipeSingleFrame, will be removed after v29.
   injected_apPipe:
     subset:
     - inject_visit

pipelines/_ingredients/SingleFrame.yaml

@@ -2,8 +2,7 @@ description: Single-frame pipeline for the case in which no templates exist
 imports:
   - location: $AP_PIPE_DIR/pipelines/_ingredients/ApPipe.yaml
     include:
-      - processCcd
-      - initialPviCore
+      - apPipeSingleFrame
       - getRegionTimeFromVisit
       - mpSkyEphemerisQuery
 tasks: