feat(workflows): M1 — schema + definition validation + declarative reconcile

First milestone of the v1.2 Workflows track (blueprint §9.1/§9.2): the durable
DAG engine's foundation — the definition model, its validation, and the
declarative `apply` reconcile path. No execution yet (the orchestrator is M2).

- Migration 0071_workflows: `workflows` (owner-polymorphic like scripts, app-
  owned in M1), `workflow_runs`, and `workflow_run_steps` (the per-step
  competing-consumer lease table the M2 orchestrator will claim). Schema golden
  reblessed.
- `shared::workflow`: the `WorkflowDefinition` / `WorkflowStepDef` DTOs (shared
  by the CLI, apply, and the future orchestrator) + run/step status enums.
- Pure, DB-free `workflow_template` (input `{{ input.x }}` / `{{ steps.a.output.y }}`
  resolution, type-preserving) and `workflow_expr` (a small safe JSON-predicate
  evaluator for `when` — keeps manager-core free of a scripting engine).
- `workflow_repo`: read trait + reconcile tx free-fns (insert/update/delete).
- apply_service: `BundleWorkflow` + `Plan.workflows` + `CurrentState.workflows`
  + `ApplyReport.workflows_*`; server-side `validate_workflow_definition`
  (unique/acyclic steps via topological sort, deps exist, function XOR workflow,
  `when`/template parse) rejecting on a group node; `diff_workflows` by
  lower(name) (Update on a definition change) + in-tx reconcile.
- CLI: `[[workflows]]` + `[[workflows.steps]]` manifest structs → wire bundle;
  plan/apply render + report counts.
- Tests: 16 manager-core lib tests (template, expr, definition validation) +
  the `workflows` CLI journey (apply → NoOp → prune; cyclic DAG rejected).

Deferred to later milestones: the orchestrator worker (M2), conditional/template
runtime wiring (M3), nested sub-workflows (M4), the SDK/API/CLI run surface
(M5), the dashboard (M6). The `group_id` column + run/step tables ship now so
those slot in without a migration churn.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

crates/picloud-cli/src/cmds/plan.rs

@@ -106,7 +106,7 @@ fn render_tree(plan: &TreePlanDto, mode: OutputMode) {
                 ]);
             }
         }
-        let groups: [(&str, &Vec<ChangeDto>); 8] = [
+        let groups: [(&str, &Vec<ChangeDto>); 9] = [
             ("script", &n.scripts),
             ("route", &n.routes),
             ("trigger", &n.triggers),
@@ -115,6 +115,7 @@ fn render_tree(plan: &TreePlanDto, mode: OutputMode) {
             ("extension_point", &n.extension_points),
             ("collection", &n.collections),
             ("suppression", &n.suppressions),
+            ("workflow", &n.workflows),
         ];
         for (rk, changes) in groups {
             for c in changes {
@@ -246,6 +247,24 @@ pub fn build_bundle(manifest: &Manifest, base_dir: &Path) -> Result<Value> {
             .collect::<Vec<_>>(),
         "suppress_triggers": manifest.suppress.triggers,
         "suppress_routes": manifest.suppress.routes,
+        "workflows": manifest
+            .workflows
+            .iter()
+            .map(workflow_to_wire)
+            .collect::<Result<Vec<_>>>()?,
+    }))
+}
+
+/// Convert a `[[workflows]]` manifest block to the server `BundleWorkflow`
+/// shape `{ name, enabled, definition: { steps } }`. The manifest authors steps
+/// at the workflow's top level; the wire nests them under `definition`.
+fn workflow_to_wire(w: &crate::manifest::ManifestWorkflow) -> Result<Value> {
+    let steps = serde_json::to_value(&w.steps)
+        .with_context(|| format!("encoding workflow `{}`", w.name))?;
+    Ok(json!({
+        "name": w.name,
+        "enabled": w.enabled,
+        "definition": { "steps": steps },
     }))
 }
 
@@ -276,7 +295,7 @@ fn render(plan: &PlanDto, mode: OutputMode) {
             ]);
         }
     }
-    let groups: [(&str, &Vec<ChangeDto>); 8] = [
+    let groups: [(&str, &Vec<ChangeDto>); 9] = [
         ("script", &plan.scripts),
         ("route", &plan.routes),
         ("trigger", &plan.triggers),
@@ -285,6 +304,7 @@ fn render(plan: &PlanDto, mode: OutputMode) {
         ("extension_point", &plan.extension_points),
         ("collection", &plan.collections),
         ("suppression", &plan.suppressions),
+        ("workflow", &plan.workflows),
     ];
     for (kind, changes) in groups {
         for c in changes {