Trim comment essays and hoist function-local test imports

.github/actions/cache-arduino8266/action.yml

@@ -10,11 +10,9 @@ runs:
   using: composite
   steps:
     - name: Resolve the native toolchain cache key
-      # The versions are pinned in code, not in a hashable file, so resolve
-      # them for the key (actions/cache never overwrites a key, so a bump
-      # must change it). Assignment form so errexit catches a resolver
-      # failure; a nested $(...) inside echo would silently yield a
-      # degenerate key.
+      # Versions are pinned in code, not a hashable file; resolve them so a
+      # bump changes the cache key. Assignment form so errexit catches a
+      # resolver failure.
       id: version
       shell: bash
       run: |

.github/workflows/ci.yml

@@ -1166,10 +1166,7 @@ jobs:
       - determine-jobs
     if: github.event_name == 'pull_request' && needs.determine-jobs.outputs.esp8266-native == 'true'
     env:
-      # Comma-joined subset of the native-ESP8266 representative component list,
-      # computed by script/determine-jobs.py (esp8266_native_components_to_test).
-      # Single source of truth -- the full list lives in
-      # script/determine-jobs.py::ESP8266_NATIVE_TEST_COMPONENTS.
+      # Computed by script/determine-jobs.py (ESP8266_NATIVE_TEST_COMPONENTS)
       TEST_COMPONENTS: ${{ needs.determine-jobs.outputs.esp8266-native-components }}
       ESPHOME_ARDUINO8266_PREFIX: ~/.esphome-arduino8266
     steps: