feat(api): add workflow export and import endpoints to the public v1 API (#5999)

* feat(api): add workflow export and import endpoints to the public v1 API

Adds GET /api/v1/workflows/[id]/export and POST /api/v1/workflows/import.
The export envelope is accepted verbatim by import, so workflows round-trip
between workspaces over the public API.

Unlike the admin export, the public export is secret-sanitized: stored
credentials and password fields are redacted while {{ENV_VAR}} references
and block positions are preserved. Import regenerates block, edge, loop and
parallel ids and de-duplicates the workflow name against the target folder.

Also moves parseWorkflowVariables out of the admin types module into
lib/workflows/variables/parse.ts so the public route does not import from
the admin namespace.

* fix(api): make workflow import atomic and clarify what export redacts

Writes the imported graph and its variables in a single transaction and
deletes the shell workflow row on any failure, so a caller that receives an
error is never left with a partially imported workflow. Previously a throw
from the variables update returned 500 while leaving the workflow behind
with an empty variables map.

Also narrows the export route's sanitization claim: workflow variables are
emitted as stored, matching GET /api/v1/workflows/[id] and the in-app
export. They are plaintext configuration readable at the same permission
level this route requires; secrets belong in environment variables, which
travel as unresolved references.

* fix(api): close import defects found in audit and share one write pipeline

Security:
- Escape block names before interpolating them into a RegExp in
  updateValueReferences. Names reach it straight from imported workflow JSON
  and normalizeWorkflowBlockName preserves regex metacharacters, so a name
  like `a*a*a*a*b` compiled to a catastrophically backtracking pattern. A
  sub-kilobyte body blocked the event loop for 50s and grew exponentially.
  Also skip rename-to-itself, which is the entire map on the import path, so
  the scan no longer runs at all there.
- Validate folder ownership before folder lock state, so a locked folder in
  another workspace can no longer be distinguished from a missing one.

Correctness:
- Gate the imported graph on workflowStateSchema, the same schema the
  canonical PUT /api/workflows/[id]/state path enforces. Without it a valid
  201 could persist a block field of the wrong type, which then threw on
  every subsequent read and left a workflow nothing could open.
- Guard the compensating delete so a failed rollback logs the orphaned id
  instead of vanishing into a generic 500.
- Validate variable `type` against the enum and build the record on a
  null-prototype object, so a `__proto__` key no longer silently drops the
  variable.
- Bound payload-derived names and descriptions to the same limits the
  contract declares for the explicit overrides.
- Return the description as stored rather than coercing '' to null, matching
  GET /api/v1/workflows/[id].

Shared code, so the two write paths cannot drift:
- Extract prepareWorkflowStateForPersistence and use it from both
  PUT /api/workflows/[id]/state and the v1 import route: agent-tool
  sanitization, block backfill, dangling-edge removal, and loop/parallel
  recomputation now have one implementation.
- Persist inline custom tools on import, which the canonical path already did.
- Move variable normalization into lib/workflows/variables and repoint the
  admin importer at it, removing the last duplicate.

Docs:
- OpenAPI: oneOf -> anyOf on the import body. WorkflowExport matches any
  object, so every valid object payload matched two branches and failed
  validation under any spec-driven validator. Document 423 and the loss of
  workspace-scoped bindings on export.

Tests: prepare-state unit tests and a real export -> import round trip with
no mocks of the sanitizer or parser, covering loop/parallel children and the
regex-metacharacter payload.

* fix(api): cap import names inside the bound and align the three import paths

- `truncate` appends its suffix after slicing, so capping at the contract
  limit produced 203/2003-character values — past the very bound the cap
  exists to enforce, and into the headroom reserved for dedup suffixes.
  Reserve the ellipsis inside the limit.
- Match `extractWorkflowName`'s candidate order (state.metadata.name before
  workflow.name) and trim, so the v1 API and the in-app importer resolve the
  same name for the same payload. Previously a hand-authored payload carrying
  both could yield two different names.
- Run the admin importer through prepareWorkflowStateForPersistence too. It
  was writing raw parsed state, so a dangling edge tripped the workflow_edges
  foreign key and a block missing its backfilled columns could land
  unopenable — the same class this PR just closed on the v1 path.

Author: waleedlatif1

apps/docs/content/docs/en/api-reference/(generated)/workflows/meta.json

@@ -5,6 +5,8 @@
     "cancelExecution",
     "listWorkflows",
     "getWorkflow",
+    "exportWorkflow",
+    "importWorkflow",
     "deployWorkflow",
     "undeployWorkflow",
     "rollbackWorkflow",