Revert "SaaS fixes (#6578)"

This reverts commit ddf78d11ae.

.taskfiles/backend.yml

@@ -18,15 +18,6 @@ version: '3'
 tasks:
   dev:
     desc: "Start backend dev server"
-    cmds:
-      - task: dev:proprietary
-        vars:
-          PORT: '{{.PORT}}'
-          AIENGINE_URL: '{{.AIENGINE_URL}}'
-          AIENGINE_TIMEOUTSECONDS: '{{.AIENGINE_TIMEOUTSECONDS}}'
-
-  dev:proprietary:
-    desc: "Start backend dev server in proprietary mode"
     ignore_error: true
     vars:
       PORT: '{{.PORT | default "8080"}}'
@@ -59,14 +50,9 @@ tasks:
       PORT: '{{.PORT | default "8080"}}'
       # Override to "" to run the pure `saas` profile against your own SAAS_DB_*.
       PROFILES: '{{.PROFILES | default "dev"}}'
-      AIENGINE_URL: '{{.AIENGINE_URL | default ""}}'
-      AIENGINE_TIMEOUTSECONDS: '{{.AIENGINE_TIMEOUTSECONDS | default "120"}}'
     env:
       SERVER_PORT: '{{.PORT}}'
       STIRLING_FLAVOR: saas
-      AIENGINE_URL: '{{.AIENGINE_URL}}'
-      AIENGINE_ENABLED: '{{if .AIENGINE_URL}}true{{else}}false{{end}}'
-      AIENGINE_TIMEOUTSECONDS: '{{.AIENGINE_TIMEOUTSECONDS}}'
     cmds:
       - cmd: cmd /c ".\gradlew.bat :stirling-pdf:bootRun {{if .PROFILES}}--args=\"--spring.profiles.include={{.PROFILES}}\"{{end}}"
         platforms: [windows]

.taskfiles/docker.yml

@@ -20,11 +20,6 @@ tasks:
     cmds:
       - docker build -t stirling-pdf-ultra-lite -f {{.EMBEDDED_DIR}}/Dockerfile.ultra-lite .
 
-  build:backend:
-    desc: "Build backend-only Docker image (no embedded frontend)"
-    cmds:
-      - docker build -t stirling-pdf-backend -f docker/backend/Dockerfile .
-
   build:frontend:
     desc: "Build frontend-only Docker image"
     cmds:

.taskfiles/engine.yml

@@ -1,5 +1,12 @@
 version: '3'
 
+vars:
+  # Engine-specific names to avoid overriding the root Taskfile's FIND_FREE_PORT_*
+  # vars (Task merges included-file vars into the global scope).
+  # Paths are relative to the engine/ include dir.
+  ENGINE_FIND_FREE_PORT_SH: "bash ../scripts/find-free-port.sh"
+  ENGINE_FIND_FREE_PORT_PS: "powershell -NoProfile -File ../scripts/find-free-port.ps1"
+
 tasks:
   install:
     desc: "Install engine dependencies"
@@ -29,11 +36,14 @@ tasks:
     ignore_error: true
     dir: src
     vars:
-      PORT: '{{.PORT | default "5001"}}'
+      # When PORT is provided (e.g. from dev:all), use it directly.
+      # When running standalone, probe for a free port starting at 5001.
+      PORT:
+        sh: '{{if .PORT}}echo {{.PORT}}{{else if eq OS "windows"}}{{.ENGINE_FIND_FREE_PORT_PS}} 5001{{else}}{{.ENGINE_FIND_FREE_PORT_SH}} 5001{{end}}'
     env:
       PYTHONUNBUFFERED: "1"
     cmds:
-      - uv run uvicorn stirling.api.app:app --host 0.0.0.0 --port {{.PORT}} --workers "${STIRLING_ENGINE_WORKERS:-4}"
+      - uv run uvicorn stirling.api.app:app --host 0.0.0.0 --port {{.PORT}}
 
   dev:
     desc: "Start engine dev server with hot reload"
@@ -41,7 +51,10 @@ tasks:
     ignore_error: true
     dir: src
     vars:
-      PORT: '{{.PORT | default "5001"}}'
+      # When PORT is provided (e.g. from dev:all), use it directly.
+      # When running standalone, probe for a free port starting at 5001.
+      PORT:
+        sh: '{{if .PORT}}echo {{.PORT}}{{else if eq OS "windows"}}{{.ENGINE_FIND_FREE_PORT_PS}} 5001{{else}}{{.ENGINE_FIND_FREE_PORT_SH}} 5001{{end}}'
     env:
       PYTHONUNBUFFERED: "1"
     cmds: