feat(cli): pic config --effective (masked secret resolution)

The §11 Phase-1 `config --effective` surface. Single-app today, "config"
= the app's secrets, so it cross-references the manifest's declared
secret names against what's set on the server and renders each masked:
`<set>` (managed / on-server-not-in-manifest) or `<unset>` (declared but
not pushed). Values are never fetched or shown (§4.6). Shaped to grow an
`--explain` mode and inherited `vars` when groups/vars arrive (Phase 3).

Tested: a journey verifying declared-but-unset → `<unset>`, post-`secret
set` → `<set>`/managed, and the value never appears in output.

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

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

@@ -0,0 +1,50 @@
+//! `pic config --effective` — read-only view of an app's resolved
+//! configuration, with secret values masked (§4.6).
+//!
+//! Single-app today: "config" means the app's secrets, cross-referenced
+//! against the manifest so an operator can see at a glance which declared
+//! secrets are still unset and which live secrets aren't declared. Values are
+//! never fetched or shown — only `<set>` / `<unset>`. The command is shaped to
+//! grow an `--explain` mode and inherited `vars` once groups/vars land (the
+//! Phase-3 multi-level resolution).
+
+use std::collections::BTreeSet;
+use std::path::Path;
+
+use anyhow::{bail, Result};
+
+use crate::client::Client;
+use crate::config;
+use crate::manifest::Manifest;
+use crate::output::{OutputMode, Table};
+
+pub async fn run(manifest_path: &Path, effective: bool, mode: OutputMode) -> Result<()> {
+    if !effective {
+        bail!("`pic config` currently supports only `--effective`");
+    }
+    let creds = config::resolve()?;
+    let client = Client::from_creds(&creds)?;
+    let manifest = Manifest::load(manifest_path)?;
+
+    let declared: BTreeSet<String> = manifest.secrets.names.iter().cloned().collect();
+    let on_server: BTreeSet<String> = client
+        .secrets_list(&manifest.app.slug)
+        .await?
+        .secrets
+        .into_iter()
+        .map(|s| s.name)
+        .collect();
+
+    let mut table = Table::new(["secret", "value", "status"]);
+    for name in declared.union(&on_server) {
+        let (value, status) = match (declared.contains(name), on_server.contains(name)) {
+            (true, true) => ("<set>", "managed"),
+            (true, false) => ("<unset>", "declared, not pushed — `pic secret set`"),
+            (false, true) => ("<set>", "on server, not in manifest"),
+            (false, false) => unreachable!("name came from one of the two sets"),
+        };
+        table.row([name.clone(), value.to_string(), status.to_string()]);
+    }
+    table.print(mode);
+    Ok(())
+}

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

@@ -3,6 +3,7 @@ pub mod api_keys;
 pub mod apply;
 pub mod apps;
 pub mod apps_domains;
+pub mod config;
 pub mod dead_letters;
 pub mod files;
 pub mod init;