gh-40821: Devcontainer: use devcontainer id as key for venv and build directory
    
... otherwise different devcontainers would try to reuse the same
venv/build directory - which will not work as the underlying os of the
devcontainer can be quite different.

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### ⌛ Dependencies

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URL: #40821
Reported by: Tobias Diez
Reviewer(s): Dima Pasechnik

Author: Release Manager

.devcontainer/onCreate-meson.sh

@@ -2,7 +2,7 @@
 
 SYSTEM=$(build/bin/sage-guess-package-system)
 
-if [ "$SYSTEM" = "fedora" ]; then
+if [ "$SYSTEM" = "fedora" ] && [ -f /etc/fedora-release ]; then
     # Need to use --setopt=tsflags="" to avoid errors with gphelp
     dnf5 install -y pari-gp --setopt=tsflags=""
 
@@ -16,7 +16,8 @@ eval $(build/bin/sage-print-system-package-command $SYSTEM --yes --ignore-missin
 
 # Disable build isolation following the advice of https://mesonbuild.com/meson-python/how-to-guides/editable-installs.html#build-dependencies
 # Install build dependencies manually as workaround for https://github.com/astral-sh/uv/issues/1516
-uv venv
+uv venv --clear
+. $UV_PROJECT_ENVIRONMENT/bin/activate # https://github.com/astral-sh/uv/issues/14022
 uv pip install \
     meson-python \
     "cypari2 >=2.2.1" \
@@ -27,4 +28,4 @@ uv pip install \
     "numpy >=1.25" \
     jinja2 \
     setuptools
-uv sync --frozen --inexact --no-build-isolation --config-settings=builddir=build/build-$SYSTEM
+uv sync --frozen --inexact --no-build-isolation -v --config-settings=builddir=build/build-$SYSTEM-$devcontainerId

.devcontainer/portability-archlinux/devcontainer.json

@@ -13,6 +13,10 @@
 			"version": "latest"
 		}
     },
+    "containerEnv": {
+        "devcontainerId": "${devcontainerId}",
+        "UV_PROJECT_ENVIRONMENT": ".venv-${devcontainerId}" 
+    },
     "customizations": {
         "vscode": {
             "extensions": [

.devcontainer/portability-fedora-41/devcontainer.json

@@ -10,6 +10,10 @@
 			"version": "latest"
 		}
     },
+    "containerEnv": {
+        "devcontainerId": "${devcontainerId}",
+        "UV_PROJECT_ENVIRONMENT": ".venv-${devcontainerId}" 
+    },
     "customizations": {
         "vscode": {
             "extensions": [

.devcontainer/portability-fedora-42/devcontainer.json

@@ -10,6 +10,10 @@
 			"version": "latest"
 		}
     },
+    "containerEnv": {
+        "devcontainerId": "${devcontainerId}",
+        "UV_PROJECT_ENVIRONMENT": ".venv-${devcontainerId}" 
+    },
     "customizations": {
         "vscode": {
             "extensions": [

.devcontainer/portability-ubuntu-2204/devcontainer.json

@@ -10,6 +10,10 @@
 			"version": "latest"
 		}
     },
+    "containerEnv": {
+        "devcontainerId": "${devcontainerId}",
+        "UV_PROJECT_ENVIRONMENT": ".venv-${devcontainerId}" 
+    },
     "customizations": {
         "vscode": {
             "extensions": [

.devcontainer/portability-ubuntu-2404/devcontainer.json

@@ -10,6 +10,10 @@
 			"version": "latest"
 		}
     },
+    "containerEnv": {
+        "devcontainerId": "${devcontainerId}",
+        "UV_PROJECT_ENVIRONMENT": ".venv-${devcontainerId}" 
+    },
     "customizations": {
         "vscode": {
             "extensions": [

.devcontainer/portability-ubuntu-2504/devcontainer.json

@@ -10,6 +10,10 @@
 			"version": "latest"
 		}
     },
+    "containerEnv": {
+        "devcontainerId": "${devcontainerId}",
+        "UV_PROJECT_ENVIRONMENT": ".venv-${devcontainerId}" 
+    },
     "customizations": {
         "vscode": {
             "extensions": [

.devcontainer/portability-void/devcontainer.json

@@ -14,6 +14,10 @@
 			"version": "latest"
 		}
     },
+    "containerEnv": {
+        "devcontainerId": "${devcontainerId}",
+        "UV_PROJECT_ENVIRONMENT": ".venv-${devcontainerId}" 
+    },
     "customizations": {
         "vscode": {
             "extensions": [