Add SSH environment support (#4358)

## Thinking Path

> - Paperclip orchestrates AI agents for zero-human companies
> - The environments subsystem already models execution environments,
but before this branch there was no end-to-end SSH-backed runtime path
for agents to actually run work against a remote box
> - That meant agents could be configured around environment concepts
without a reliable way to execute adapter sessions remotely, sync
workspace state, and preserve run context across supported adapters
> - We also need environment selection to participate in normal
Paperclip control-plane behavior: agent defaults, project/issue
selection, route validation, and environment probing
> - Because this capability is still experimental, the UI surface should
be easy to hide and easy to remove later without undoing the underlying
implementation
> - This pull request adds SSH environment execution support across the
runtime, adapters, routes, schema, and tests, then puts the visible
environment-management UI behind an experimental flag
> - The benefit is that we can validate real SSH-backed agent execution
now while keeping the user-facing controls safely gated until the
feature is ready to come out of experimentation

## What Changed

- Added SSH-backed execution target support in the shared adapter
runtime, including remote workspace preparation, skill/runtime asset
sync, remote session handling, and workspace restore behavior after
runs.
- Added SSH execution coverage for supported local adapters, plus remote
execution tests across Claude, Codex, Cursor, Gemini, OpenCode, and Pi.
- Added environment selection and environment-management backend support
needed for SSH execution, including route/service work, validation,
probing, and agent default environment persistence.
- Added CLI support for SSH environment lab verification and updated
related docs/tests.
- Added the `enableEnvironments` experimental flag and gated the
environment UI behind it on company settings, agent configuration, and
project configuration surfaces.

## Verification

- `pnpm exec vitest run
packages/adapters/claude-local/src/server/execute.remote.test.ts
packages/adapters/cursor-local/src/server/execute.remote.test.ts
packages/adapters/gemini-local/src/server/execute.remote.test.ts
packages/adapters/opencode-local/src/server/execute.remote.test.ts
packages/adapters/pi-local/src/server/execute.remote.test.ts`
- `pnpm exec vitest run server/src/__tests__/environment-routes.test.ts`
- `pnpm exec vitest run
server/src/__tests__/instance-settings-routes.test.ts`
- `pnpm exec vitest run ui/src/lib/new-agent-hire-payload.test.ts
ui/src/lib/new-agent-runtime-config.test.ts`
- `pnpm -r typecheck`
- `pnpm build`
- Manual verification on a branch-local dev server:
  - enabled the experimental flag
  - created an SSH environment
  - created a Linux Claude agent using that environment
- confirmed a run executed on the Linux box and synced workspace changes
back

## Risks

- Medium: this touches runtime execution flow across multiple adapters,
so regressions would likely show up in remote session setup, workspace
sync, or environment selection precedence.
- The UI flag reduces exposure, but the underlying runtime and route
changes are still substantial and rely on migration correctness.
- The change set is broad across adapters, control-plane services,
migrations, and UI gating, so review should pay close attention to
environment-selection precedence and remote workspace lifecycle
behavior.

## Model Used

- OpenAI Codex via Paperclip's local Codex adapter, GPT-5-class coding
model with tool use and code execution in the local repo workspace. The
local adapter does not surface a more specific public model version
string in this branch workflow.

## Checklist

- [x] I have included a thinking path that traces from project context
to this change
- [x] I have specified the model used (with version and capability
details)
- [x] I have checked ROADMAP.md and confirmed this PR does not duplicate
planned core work
- [x] I have run tests locally and they pass
- [x] I have added or updated tests where applicable
- [ ] If this change affects the UI, I have included before/after
screenshots
- [x] I have updated relevant documentation to reflect my changes
- [x] I have considered and documented any risks above
- [x] I will address all Greptile and reviewer comments before
requesting merge

packages/shared/src/validators/agent.ts

@@ -55,6 +55,7 @@ export const createAgentSchema = z.object({
   adapterType: agentAdapterTypeSchema,
   adapterConfig: adapterConfigSchema.optional().default({}),
   runtimeConfig: z.record(z.unknown()).optional().default({}),
+  defaultEnvironmentId: z.string().uuid().optional().nullable(),
   budgetMonthlyCents: z.number().int().nonnegative().optional().default(0),
   permissions: agentPermissionsSchema.optional(),
   metadata: z.record(z.unknown()).optional().nullable(),

packages/shared/src/validators/environment.ts

@@ -32,3 +32,12 @@ export const updateEnvironmentSchema = z.object({
   metadata: z.record(z.unknown()).optional().nullable(),
 }).strict();
 export type UpdateEnvironment = z.infer<typeof updateEnvironmentSchema>;
+
+export const probeEnvironmentConfigSchema = z.object({
+  name: z.string().min(1).optional(),
+  description: z.string().optional().nullable(),
+  driver: environmentDriverSchema,
+  config: z.record(z.unknown()).optional().default({}),
+  metadata: z.record(z.unknown()).optional().nullable(),
+}).strict();
+export type ProbeEnvironmentConfig = z.infer<typeof probeEnvironmentConfigSchema>;

packages/shared/src/validators/execution-workspace.ts

@@ -9,6 +9,7 @@ export const executionWorkspaceStatusSchema = z.enum([
 ]);
 
 export const executionWorkspaceConfigSchema = z.object({
+  environmentId: z.string().uuid().optional().nullable(),
   provisionCommand: z.string().optional().nullable(),
   teardownCommand: z.string().optional().nullable(),
   cleanupCommand: z.string().optional().nullable(),

packages/shared/src/validators/index.ts

@@ -31,8 +31,10 @@ export {
   environmentLeaseCleanupStatusSchema,
   createEnvironmentSchema,
   updateEnvironmentSchema,
+  probeEnvironmentConfigSchema,
   type CreateEnvironment,
   type UpdateEnvironment,
+  type ProbeEnvironmentConfig,
 } from "./environment.js";
 export {
   feedbackDataSharingPreferenceSchema,

packages/shared/src/validators/instance.ts

@@ -33,6 +33,7 @@ export const instanceGeneralSettingsSchema = z.object({
 export const patchInstanceGeneralSettingsSchema = instanceGeneralSettingsSchema.partial();
 
 export const instanceExperimentalSettingsSchema = z.object({
+  enableEnvironments: z.boolean().default(false),
   enableIsolatedWorkspaces: z.boolean().default(false),
   autoRestartDevServerWhenIdle: z.boolean().default(false),
 }).strict();

packages/shared/src/validators/issue.ts

@@ -34,6 +34,7 @@ const executionWorkspaceStrategySchema = z
 export const issueExecutionWorkspaceSettingsSchema = z
   .object({
     mode: z.enum(ISSUE_EXECUTION_WORKSPACE_PREFERENCES).optional(),
+    environmentId: z.string().uuid().optional().nullable(),
     workspaceStrategy: executionWorkspaceStrategySchema.optional().nullable(),
     workspaceRuntime: z.record(z.unknown()).optional().nullable(),
   })

packages/shared/src/validators/project.ts

@@ -19,6 +19,7 @@ export const projectExecutionWorkspacePolicySchema = z
     defaultMode: z.enum(["shared_workspace", "isolated_workspace", "operator_branch", "adapter_default"]).optional(),
     allowIssueOverride: z.boolean().optional(),
     defaultProjectWorkspaceId: z.string().uuid().optional().nullable(),
+    environmentId: z.string().uuid().optional().nullable(),
     workspaceStrategy: executionWorkspaceStrategySchema.optional().nullable(),
     workspaceRuntime: z.record(z.unknown()).optional().nullable(),
     branchPolicy: z.record(z.unknown()).optional().nullable(),