Run python nodes out of process, with modules of their own

User code no longer execs in the engine. A pool of persistent worker
subprocesses speaks one JSON object per line; the controller installs a
proxy as the node's function, so every execution path funnels through it
and the pipeline is untouched. A crash costs one subprocess, a per-node
timeout is a kill, and cancelling from the canvas is that same kill.

The workers run a venv of the user's own on the data volume, filled from
a pip manifest versioned beside the flows. Applying it retires the
workers and rebuilds, so a package lands without restarting the engine.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_017MeiWk3Yq12n2pTvnQWYvt

frontend/src/client/schemas.gen.ts

@@ -27,6 +27,36 @@ export const AlertsConfigSchema = {
     description: 'The whole alerting setup, as stored and as the API sees it.'
 } as const;
 
+export const ApplyRequestSchema = {
+    properties: {
+        requirements: {
+            type: 'string',
+            title: 'Requirements',
+            default: ''
+        }
+    },
+    type: 'object',
+    title: 'ApplyRequest',
+    description: 'A pip manifest, one requirement per line.'
+} as const;
+
+export const ApplyResultSchema = {
+    properties: {
+        ok: {
+            type: 'boolean',
+            title: 'Ok'
+        },
+        output: {
+            type: 'string',
+            title: 'Output',
+            default: ''
+        }
+    },
+    type: 'object',
+    required: ['ok'],
+    title: 'ApplyResult'
+} as const;
+
 export const Body_login_login_access_tokenSchema = {
     properties: {
         grant_type: {
@@ -890,6 +920,58 @@ export const MessagesPublicSchema = {
     title: 'MessagesPublic'
 } as const;
 
+export const ModulePackageSchema = {
+    properties: {
+        name: {
+            type: 'string',
+            title: 'Name'
+        },
+        version: {
+            type: 'string',
+            title: 'Version'
+        }
+    },
+    type: 'object',
+    required: ['name', 'version'],
+    title: 'ModulePackage',
+    description: 'One package installed in the venv node code runs on.'
+} as const;
+
+export const ModulesInfoSchema = {
+    properties: {
+        python_version: {
+            type: 'string',
+            title: 'Python Version',
+            default: ''
+        },
+        venv_path: {
+            type: 'string',
+            title: 'Venv Path',
+            default: ''
+        },
+        requirements: {
+            type: 'string',
+            title: 'Requirements',
+            default: ''
+        },
+        packages: {
+            items: {
+                '$ref': '#/components/schemas/ModulePackage'
+            },
+            type: 'array',
+            title: 'Packages'
+        },
+        applied: {
+            type: 'boolean',
+            title: 'Applied',
+            default: false
+        }
+    },
+    type: 'object',
+    title: 'ModulesInfo',
+    description: 'The venv node code imports from, and the manifest that describes it.'
+} as const;
+
 export const NewPasswordSchema = {
     properties: {
         token: {
@@ -960,6 +1042,19 @@ export const NodeDef_InputSchema = {
                 }
             ],
             title: 'Source Ref'
+        },
+        timeout: {
+            anyOf: [
+                {
+                    type: 'number',
+                    exclusiveMinimum: 0
+                },
+                {
+                    type: 'null'
+                }
+            ],
+            title: 'Timeout',
+            description: "Seconds this node's code may run before it is stopped. Above 60 the engine may deliver its work again while it is still running."
         }
     },
     type: 'object',
@@ -1020,6 +1115,19 @@ export const NodeDef_OutputSchema = {
                 }
             ],
             title: 'Source Ref'
+        },
+        timeout: {
+            anyOf: [
+                {
+                    type: 'number',
+                    exclusiveMinimum: 0
+                },
+                {
+                    type: 'null'
+                }
+            ],
+            title: 'Timeout',
+            description: "Seconds this node's code may run before it is stopped. Above 60 the engine may deliver its work again while it is still running."
         }
     },
     type: 'object',