feat(secrets): group-secrets admin API, masked read, config/effective

Adds the Phase-3 admin surface on top of the group-secrets storage:

* `secrets_api` gains group routes under `/groups/{id}/secrets`
  (set/list/delete, env-scoped) gated `GroupSecretsWrite` (editor+), plus
  the ONE plaintext endpoint `GET /groups/{id}/secrets/{name}/value` gated
  `GroupSecretsRead` (group_admin only). That is the masked-secret
  boundary: a descendant app's dev sees a group secret EXISTS and consumes
  it at runtime via `secrets::get`, but only a reader at the OWNING group
  gets the value. App secrets stay env-agnostic (a stray `env` is rejected).
  The owner is resolved first, then the capability binds to the resolved
  id — never a path param.

* `config_api`: `GET /apps/{id}/config/effective` (gated `AppVarsRead`)
  returns the resolved view a dev would get — every inherited var with its
  value + provenance, and every inherited secret MASKED (name/owner/scope,
  never the value). Backed by a new `fetch_effective_secret_meta`
  (DISTINCT-ON nearest-wins, same ordering as the per-name resolver).

* authz: `GroupSecretsWrite` moves from `app:admin` to `script:write`
  scope so its API-key scope matches its editor role tier (closing the
  latent scope/role mismatch the checkpoint review flagged); the value
  read `GroupSecretsRead` stays at `app:admin`.

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

crates/manager-core/src/config_api.rs

@@ -0,0 +1,158 @@
+//! `GET /api/v1/admin/apps/{id}/config/effective` — the resolved config an
+//! app actually sees: every inherited var (with its value + provenance) and
+//! every inherited secret (MASKED — name/owner/scope only, never the value).
+//!
+//! This is the read-only companion to the `vars`/`secrets` admin surfaces.
+//! It runs the same §3 resolution the `vars::`/`secrets::` SDK calls run, so
+//! a dev can see exactly what `vars::get`/`secrets::get` would return and
+//! where each value comes from (`--explain` on the CLI surfaces the
+//! provenance). Gated by `AppVarsRead` (config is app-readable); the secret
+//! VALUES are deliberately absent — reading those needs `GroupSecretsRead`
+//! at the owning group via the dedicated value endpoint.
+
+use std::sync::Arc;
+
+use axum::extract::{Path, State};
+use axum::http::StatusCode;
+use axum::response::{IntoResponse, Json, Response};
+use axum::routing::get;
+use axum::{Extension, Router};
+use picloud_shared::{AppId, Principal};
+use serde_json::json;
+use sqlx::PgPool;
+
+use crate::app_repo::AppRepository;
+use crate::authz::{require, AuthzDenied, AuthzError, AuthzRepo, Capability};
+use crate::config_resolver::{
+    fetch_effective_secret_meta, fetch_var_candidates, resolve, OwnerKind,
+};
+
+#[derive(Clone)]
+pub struct ConfigApiState {
+    pub pool: PgPool,
+    pub apps: Arc<dyn AppRepository>,
+    pub authz: Arc<dyn AuthzRepo>,
+}
+
+pub fn config_router(state: ConfigApiState) -> Router {
+    Router::new()
+        .route("/apps/{id_or_slug}/config/effective", get(effective_config))
+        .with_state(state)
+}
+
+fn owner_json(kind: OwnerKind, id: uuid::Uuid, depth: i32) -> serde_json::Value {
+    json!({ "kind": kind.as_str(), "id": id, "depth": depth })
+}
+
+async fn effective_config(
+    State(s): State<ConfigApiState>,
+    Extension(principal): Extension<Principal>,
+    Path(id_or_slug): Path<String>,
+) -> Result<Json<serde_json::Value>, ConfigApiError> {
+    let app_id = resolve_app(&*s.apps, &id_or_slug).await?;
+    require(
+        s.authz.as_ref(),
+        &principal,
+        Capability::AppVarsRead(app_id),
+    )
+    .await?;
+
+    // Vars: resolve to values + provenance (vars are app-readable config).
+    let candidates = fetch_var_candidates(&s.pool, app_id)
+        .await
+        .map_err(|e| ConfigApiError::Backend(e.to_string()))?;
+    let (values, provenance) = resolve(candidates);
+    let mut vars = serde_json::Map::new();
+    for (key, value) in values {
+        let p = &provenance[&key];
+        vars.insert(
+            key,
+            json!({
+                "value": value,
+                "owner": owner_json(p.owner_kind, p.owner_id, p.depth),
+                "scope": p.scope,
+                "merged_from": p.merged_from
+                    .iter()
+                    .map(|(d, sc)| json!({ "depth": d, "scope": sc }))
+                    .collect::<Vec<_>>(),
+            }),
+        );
+    }
+
+    // Secrets: masked — name + owner/level/scope + status, never the value.
+    let secret_meta = fetch_effective_secret_meta(&s.pool, app_id)
+        .await
+        .map_err(|e| ConfigApiError::Backend(e.to_string()))?;
+    let mut secrets = serde_json::Map::new();
+    for m in secret_meta {
+        secrets.insert(
+            m.name,
+            json!({
+                "status": "set",
+                "owner": owner_json(m.owner_kind, m.owner_id, m.depth),
+                "scope": m.scope,
+            }),
+        );
+    }
+
+    Ok(Json(json!({ "vars": vars, "secrets": secrets })))
+}
+
+async fn resolve_app(apps: &dyn AppRepository, ident: &str) -> Result<AppId, ConfigApiError> {
+    crate::app_repo::resolve_app(apps, ident)
+        .await
+        .map_err(|e| ConfigApiError::Backend(e.to_string()))?
+        .map(|l| l.app.id)
+        .ok_or(ConfigApiError::AppNotFound)
+}
+
+#[derive(Debug, thiserror::Error)]
+pub enum ConfigApiError {
+    #[error("app not found")]
+    AppNotFound,
+    #[error("forbidden")]
+    Forbidden,
+    #[error("authorization repo error: {0}")]
+    AuthzRepo(String),
+    #[error("config backend: {0}")]
+    Backend(String),
+}
+
+impl From<AuthzDenied> for ConfigApiError {
+    fn from(d: AuthzDenied) -> Self {
+        match d {
+            AuthzDenied::Denied => Self::Forbidden,
+            AuthzDenied::Repo(e) => Self::AuthzRepo(e.to_string()),
+        }
+    }
+}
+
+impl From<AuthzError> for ConfigApiError {
+    fn from(e: AuthzError) -> Self {
+        Self::AuthzRepo(e.to_string())
+    }
+}
+
+impl IntoResponse for ConfigApiError {
+    fn into_response(self) -> Response {
+        let (status, body) = match &self {
+            Self::AppNotFound => (StatusCode::NOT_FOUND, json!({ "error": self.to_string() })),
+            Self::Forbidden => (StatusCode::FORBIDDEN, json!({ "error": self.to_string() })),
+            Self::AuthzRepo(e) => {
+                tracing::error!(error = %e, "config effective authz repo error");
+                (
+                    StatusCode::INTERNAL_SERVER_ERROR,
+                    json!({ "error": "internal error" }),
+                )
+            }
+            Self::Backend(e) => {
+                tracing::error!(error = %e, "config effective backend error");
+                (
+                    StatusCode::INTERNAL_SERVER_ERROR,
+                    json!({ "error": "internal error" }),
+                )
+            }
+        };
+        (status, Json(body)).into_response()
+    }
+}